VShips - Chemical Tanker Manual - 2004

CHEMICAL TANKER MANUAL SECTION - INTRODUCTION

Document Number Section Revision Number Page Number

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VMS/CHM/01 01 1 of 9

CHEMICAL TANKER OPERATING MANUAL VMS/CHM/01 COPY No

NOTES 1.

This Manual is valid from the issue date.

2.

This Manual is to be used only on V Ships managed vessels.

3.

This Manual is not to be copied or marked up.

4.

Review of this Manual or any suggested alteration is to be referred to the appropriate management office.

5.

Further revisions of this Manual will be recorded on the Revision Sheet (Page 2). MANAGING DIRECTOR

DIVISIONAL DIRECTOR RISK, SAFETY & QUALITY

Copyright 2004 V Ships. All rights strictly reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without the prior written permission of V Ships. Any person infringing the copyright of the V Ships will be liable to criminal prosecution and a civil claim for damages.



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REVISION SHEET 1.

When it becomes necessary to revise this manual revision will be made by the issue of the new relevant section.

2.

These revised pages will bear a new revision number that must be entered on this revision sheet and initialled by the Master or responsible manager after insertion into this book

Document Number

Section

Revision Number

Date Inserted

Manager’s or Master’s Initials



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Table of Contents 1. GENERAL..................................................................................................... 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9

Definitions.................................................................................................................1 Introduction..............................................................................................................6 Departure from these Procedures ............................................................................7 VMS manuals ............................................................................................................7 Checklists..................................................................................................................7 Reference Publications .............................................................................................7 Company Forms ........................................................................................................8 Abbreviations............................................................................................................9 Applicability ............................................................................................................11

2. RESPONSIBILITIES .................................................................................... 1 2.1 2.2 2.3 2.4 2.5 2.6 2.7

General......................................................................................................................1 Master .......................................................................................................................1 Chief Officer ..............................................................................................................1 Second Officer and Third Officer ..............................................................................2 Chief Engineer...........................................................................................................2 Pumpman..................................................................................................................2 Ratings......................................................................................................................2

3. SAFETY........................................................................................................ 1 3.1 3.2 3.3

3.4

3.5

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Chemical Hazards .....................................................................................................1 3.3.1 General ............................................................................................................. 1 3.3.2 Flammability ...................................................................................................... 2 3.3.3 Toxicity.............................................................................................................. 2 3.3.4 Asphyxia............................................................................................................ 2 3.3.5 Anaesthesia ....................................................................................................... 3 3.3.6 Reactivity........................................................................................................... 3 3.3.7 Corrositivity........................................................................................................ 4 3.3.8 Putrefaction ....................................................................................................... 4 Physical Properties Of Chemicals .............................................................................4 3.4.1 Specific Gravity (Density) .................................................................................... 4 3.4.2 Flash Point......................................................................................................... 4 3.4.3 Auto Ignition Temperature .................................................................................. 4 3.4.4 Flammable / Explosive Limits............................................................................... 4 3.4.5 Vapour pressure/Boiling point.............................................................................. 5 3.4.6 Freezing point .................................................................................................... 5 3.4.7 Pour Point.......................................................................................................... 5 3.4.8 Viscosity ............................................................................................................ 5 3.4.9 Cubic expansion ................................................................................................. 6 3.4.10 Vapour density ................................................................................................... 6 3.4.11 Solubility............................................................................................................ 6 3.4.12 Colour ............................................................................................................... 6 3.4.13 Electrostatic charging.......................................................................................... 6 General Precautions..................................................................................................6 3.5.1 General ............................................................................................................. 6 3.5.2 Cargo Information .............................................................................................. 7 3.5.3 Personnel protection ........................................................................................... 7


3.6

3.7 3.8 3.9 3.10 3.11 3.12

3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20


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3.5.4 Moorings ........................................................................................................... 7 3.5.5 Emergency towing-off wires (fire wires) ............................................................... 7 3.5.6 Means of Access and Escape (Gangways or Accommodation Ladders etc.) .............. 7 3.5.7 Unauthorised Persons ......................................................................................... 8 3.5.8 Persons Smoking or Intoxicated........................................................................... 8 3.5.9 Permanent Notices ............................................................................................. 8 3.5.10 Temporary Notices and signals ............................................................................ 9 3.5.11 Craft Alongside................................................................................................... 9 3.5.12 Wind conditions.................................................................................................. 9 3.5.13 Electrical Storms................................................................................................. 9 3.5.14 Cold weather.................................................................................................... 10 3.5.15 Openings in deckhouses and superstructures ...................................................... 10 3.5.16 Engine Room Equipment ................................................................................... 10 3.5.17 Excluding Vapour from Machinery Spaces ........................................................... 10 3.5.18 Enclosed Spaces............................................................................................... 10 3.5.19 Ship’s Readiness to move .................................................................................. 10 3.5.20 Pollution Prevention .......................................................................................... 11 3.5.21 Tank-cleaning/gas-freeing ................................................................................. 11 3.5.22 Tank-cleaning Chemicals ................................................................................... 11 3.5.23 Communication Equipment................................................................................ 11 3.5.24 Fire Fighting Equipment .................................................................................... 11 Static Electricity......................................................................................................12 3.6.1 General ........................................................................................................... 12 3.6.2 Cargo Operations ............................................................................................. 12 3.6.3 Electrical Continuity - Bonding and Earthing........................................................ 13 3.6.4 Cargo Flow Velocity .......................................................................................... 13 3.6.5 Ullaging and Sampling ...................................................................................... 14 3.6.6 Loading Overall (Splash filling) (free Fall Loading) ............................................... 14 3.6.7 Pipeline and Hose Clearing ................................................................................ 14 3.6.8 Steaming Operations ........................................................................................ 14 3.6.9 Tank Washing with Water ................................................................................. 14 3.6.10 Portable Pumps ............................................................................................... 15 3.6.11 Tanker Explosions ............................................................................................ 15 Removable Bends, Spool Pieces and Flexible Hoses ..............................................16 Flame Arrestors.......................................................................................................17 Electrical Equipment/Fittings. ................................................................................17 Hydrocarbon And toxic Gas Monitoring..................................................................17 Sounding Routines..................................................................................................17 Cargo Pumprooms ..................................................................................................18 3.12.1 Ventilation ....................................................................................................... 18 3.12.2 Routine Inspection............................................................................................ 18 3.12.3 Entry Procedures................................................................................................ 18 Void Spaces/Duct Keels and Pipe Tunnels .............................................................19 Leakage into Void and Ballast Spaces ....................................................................20 Works in Cargo and Ballast Tanks ..........................................................................20 Accidental Spillages ................................................................................................20 Sea Valves and Overboard Discharge Valves .........................................................21 Deck Scuppers ........................................................................................................21 Manifold Savealls ....................................................................................................21 Ship to Ship Transfer ..............................................................................................22 3.20.1 General ........................................................................................................... 22 3.20.2 STS at the roads / at sea .................................................................................. 22 3.20.3 Responsibility ................................................................................................... 22 3.20.4 Communications............................................................................................... 22 3.20.5 Operational considerations ................................................................................ 22 3.20.6 Notification of authorities .................................................................................. 22 3.20.7 Cargo transfer operations.................................................................................. 23



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3.20.8 Emergency....................................................................................................... 23

4. CARGO PLANNING, HANDLING AND STOWAGE.......................................... 1 4.1 4.2 4.3 4.4 4.5 4.6

4.7 4.8 4.10 4.11 4.12

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 General......................................................................................................................1 Responsibility ...........................................................................................................2 General cycle of cargo operations ............................................................................2 Voyage Planning & Stowing of Cargo .......................................................................3 4.6.1 Description ........................................................................................................ 3 4.6.2 Delivery of voyage orders.................................................................................... 3 4.6.3 Voyage Orders Contents ..................................................................................... 3 4.6.4 Cargo quantities ................................................................................................. 4 4.6.5 Filling limits........................................................................................................ 4 4.6.6 Cargo Quantity Options....................................................................................... 4 4.6.7 Cargo equipment defects .................................................................................... 5 4.6.8 Stowage Limitations of Cargo Tank Structure and Fittings on Chemical Ships........... 5 4.6.9 Oil and Hazardous Material Transfer Procedure ..................................................... 5 4.6.10 Cargo Loading/Discharge Plan ............................................................................. 5 Retention of Slops on Chemical Tankers ..................................................................6 Planning of equipment, bunkers, stores etc.............................................................6 Vapour Emission Control (VEC) Systems ..................................................................7 Ship-to-Ship (STS) Transfer using VEC Systems ......................................................8 Pre-Transfer Survey and Log Entries........................................................................9

5. SAFE STABILITY.......................................................................................... 1 5.1 5.2 5.3 5.4 5.5 5.6 5.7

Reference Publications .............................................................................................1 Checklists..................................................................................................................1 Company Forms ........................................................................................................1 General......................................................................................................................1 Stress Monitoring System.........................................................................................1 Stability of Double Hull Vessels (without centre line bulkheads) ...........................2 Slack Tanks and Sloshing .........................................................................................3

6. PREPARATION FOR LOADING AND LOADING OPERATIONS ...................... 1 6.1 6.2 6.3 6.4

6.5

6.6 6.7

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Preparation for loading operations...........................................................................1 Technical Readiness .................................................................................................2 6.4.1 Visual ................................................................................................................ 2 6.4.2 Tests / Checks ................................................................................................... 2 6.4.3 Preparation ........................................................................................................ 2 6.4.4 Safety................................................................................................................ 2 6.4.5 Cleanliness......................................................................................................... 2 Tank Acceptance & Preparation ...............................................................................3 6.5.1 General ............................................................................................................. 3 6.5.2 Visual inspection................................................................................................. 3 6.5.3 Odour check ...................................................................................................... 3 6.5.4 Wall wash tests .................................................................................................. 3 6.5.5 Wallwash procedure ........................................................................................... 4 Vessel - Surveyor agreements ..................................................................................5 Cargo Sampling.........................................................................................................5 6.7.1 General ............................................................................................................. 5 6.7.2 Safety................................................................................................................ 6 6.7.3 Labels ............................................................................................................... 6 6.7.4 Storage of samples ............................................................................................. 6 6.7.5 Sampling on land................................................................................................ 7 6.7.6 Sampling on board ............................................................................................. 7


6.8 6.9 6.10

6.11


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6.7.7 Sampling cargo under nitrogen blanket ................................................................ 7 6.7.8 Sampling programme.......................................................................................... 7 Pre-Loading Meeting ................................................................................................8 6.8.1 General ............................................................................................................. 8 6.8.2 Vessel –terminal agreements ............................................................................... 8 Preparation before cargo loading .............................................................................9 6.9.1 General ............................................................................................................. 9 6.9.2 The following important pre-loading checks are to be made by the ship: ................. 9 Closed Loading Operations .....................................................................................10 6.10.1 Purpose and scope ........................................................................................... 10 6.10.2 Company procedure.......................................................................................... 11 6.10.3 Gauging, sounding and sampling ....................................................................... 11 6.10.4 Cargo tank venting ........................................................................................... 11 6.10.5 Vapour return .................................................................................................. 11 6.10.6 Customers’ requirements................................................................................... 11 Loading Operations.................................................................................................12 6.11.1 General ........................................................................................................... 12 6.11.2 Commencement and execution of loading........................................................... 12 6.11.3 Completion of loading and final measurements ................................................... 12 6.11.4 Blowing lines.................................................................................................... 13 6.11.5 Pigging ............................................................................................................ 13 6.11.6 Disconnecting of loading arm/cargo hose ........................................................... 14 6.11.7 Measuring Ullaging ........................................................................................... 14 6.11.8 Measuring Temperature .................................................................................... 14 6.11.9 Measuring Water .............................................................................................. 15 6.11.10 Nitrogen cover ................................................................................................. 15 6.11.11 Preparation for sea voyage............................................................................ 15

7. CARGO CARE ............................................................................................... 1 7.1 7.2 7.3

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Cargo Care Requirements.........................................................................................1 7.3.1 Heating ............................................................................................................. 2 7.3.2 Cooling/Refigeration ........................................................................................... 3 7.3.3 Nitrogen blanket................................................................................................. 3 7.3.3 Oxygen.............................................................................................................. 4 7.3.4 Agitation/Re-circulation ....................................................................................... 4

8.0

PREPARATION FOR DISCHARGE AND DISCHARGING ........................... 1

8.7

PRE-DISCHARGE MEETING .................................................................... 3

8.1 8.2 8.3 8.4 8.5 8.6

8.8

8.9

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Purpose and Scope ...................................................................................................1 Technical readiness ..................................................................................................1 Safety........................................................................................................................2 Ullaging and sampling ..............................................................................................2 8.7.1 General ............................................................................................................. 3 8.7.2 Vessel –terminal agreements ............................................................................... 3 8.7.3 Vessel - surveyor agreements.............................................................................. 3 Closed Unloading Operations ...................................................................................4 8.8.1 General ............................................................................................................. 4 8.8.2 Company procedure............................................................................................ 4 8.8.3 Gauging, sounding and sampling ......................................................................... 4 8.8.4 Cargo tank venting ............................................................................................. 4 8.8.5 Vapour return .................................................................................................... 5 8.8.6 Customers’ requirements..................................................................................... 5 Discharge ..................................................................................................................5


8.10

9.0

9.1 9.2 9.3 9.4 9.5 9.6 9.7


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8.9.1 Discharging agreements...................................................................................... 5 Measures to be taken for special cargoes ................................................................7 8.10.1 Ballast and heated cargoes.................................................................................. 7 8.10.2 Discharging cargoes under nitrogen cover ............................................................ 7 8.10.3 Discharge of high viscosity products..................................................................... 7 8.10.4 Discharge of cargoes with high melting points....................................................... 7 8.10.5 Efficient stripping in accordance with P&A Manual ................................................. 7 8.10.7 Prewash according to MARPOL Annex II ............................................................... 8

INERTING AND GASFREEING OF CARGO TANKS ................................... 1

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Policy ........................................................................................................................1 Inerting/Purging ......................................................................................................2 Before use of shipboard generated Inert GAs ..........................................................2 Failure of the Inert Gas System................................................................................3 Maintenance .............................................................................................................4 9.7.1 Deck Seal .......................................................................................................... 4 9.7.2 P/V Breaker ....................................................................................................... 4 9.7.3 Inert Gas Scrubber ............................................................................................. 4 9.7.4 Non Return Valves.............................................................................................. 5 9.7.5 Flue Gas and Recirculating Valves ....................................................................... 5 Gasfreeing.................................................................................................................5 9.8.1 General ............................................................................................................. 5 9.8.2 Gasfreeing Precautions ....................................................................................... 6

9.8

10.

CARGO AND BALLAST PUMPS ................................................................ 1

11.

TANK CLEANING .................................................................................... 1

10.1 10.2 10.3

Reference Publications .............................................................................................1 General......................................................................................................................1 Pump Descriptions....................................................................................................1 10.3.1 Centrifugal Pumps .............................................................................................. 1 10.3.2 Positive Displacement Pump ................................................................................ 2 10.3.3 Submerged Pumps ............................................................................................. 2 10.3.4 Portable Submersible (Emergency) Pump ............................................................. 2 10.4 Starting and Stopping Pumps ...................................................................................3 10.5 Emergency Stopping of pumps .................................................................................3 10.6 Control and Operation of Centrifugal Pumps ...........................................................3 10.6.1 Discharge Valves ................................................................................................ 4 10.6.2 Self Priming ....................................................................................................... 4 10.7 Cavitation..................................................................................................................5 10.8 Pump Operation Parameters ....................................................................................5 10.8.1 Overloading ....................................................................................................... 5 10.8.2 Underloading ..................................................................................................... 6 10.8.3 Pump Characteristic Diagram............................................................................... 6 10.8.4 Balancing/Discharging Using More Than One Pump ............................................... 6 10.9 Submersible Pump Purging Routines .......................................................................7 10.10 Eductors ....................................................................................................................7 11.1 11.2 11.3 11.4

11.5

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Tank Cleaning Instructions.......................................................................................1 Tank Cleaning ...........................................................................................................1 11.4.1 General ............................................................................................................. 1 11.4.2 Safety requirements ........................................................................................... 2 11.4.3 Water white standard ......................................................................................... 3 Preparation for tankwashing....................................................................................3 11.5.1 Cleaning program and plan ................................................................................. 3


11.6

12.

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11.5.2 Tankwashing briefing.......................................................................................... 4 Special cleaning precautions ....................................................................................5 11.6.1 Cleaning of flammable products ........................................................................... 5 11.6.2 Cleaning of toxic products ................................................................................... 5 11.6.3 Tankcleaning Slops ............................................................................................. 5 11.6.4 Cleaning coated tanks......................................................................................... 5

BALLAST OPERATIONS........................................................................... 1

12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 12.9

12.10 12.11 12.12 12.13

12.14 12.15

13.


Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 General......................................................................................................................1 Designated Officer ....................................................................................................1 Planning of the Ballast Operations ...........................................................................2 Records and Reporting .............................................................................................2 Controls Applied by Port State Authorities...............................................................2 Loading of Ballast Water ..........................................................................................3 12.8.1 Ballasting of Cargo Tanks .................................................................................... 3 Ballast Water Exchange and Sediment Removal......................................................3 12.9.1 Flow Through Exchanges .................................................................................... 4 12.9.2 Discharge of Ballast Water in Cargo Tanks............................................................ 4 Discharge of Ballast Water .......................................................................................4 12.10.1 Discharge of Ballast Water to Shore Reception Facilities......................................... 5 Sample Analysis Certificate ......................................................................................5 Manual Removal of Solid Elements ..........................................................................6 Ballast Operation Precautions ..................................................................................6 12.13.1 Personnel Safety ................................................................................................ 6 12.13.2 Ship’s Safety ...................................................................................................... 6 12.13.3 Ballast Tank’s Venting System ............................................................................. 6 12.13.4 Pumping Limitation ............................................................................................. 7 Cathodic Protection ..................................................................................................7 Ballasting cargo tanks – Safety considerations........................................................7

EQUIPMENT ........................................................................................... 1

13.1 13.2 13.3 13.4 13.5 13.6 13.7 13.8 13.9 13.10 13.11 13.12 13.13 13.14 13.15 13.16 13.17 13.18 13.19 13.20 13.21

Reference Publications .............................................................................................1 Loading/Stress Computer.........................................................................................1 P/V Valves ................................................................................................................1 Flame Arrestor Gauzes..............................................................................................2 P/V Breaker ..............................................................................................................2 Deck Seal & Non Return Check Valves .....................................................................2 Tank Gauging............................................................................................................3 Pumproom Bilge Level Alarms ..................................................................................3 Pump Suction Strainers ............................................................................................3 Pump Safety Devices ................................................................................................3 Tank Cleaning Equipment .........................................................................................3 Gas Detection Equipment .........................................................................................3 Pressure Gauges .......................................................................................................4 Tank High Level and Overfill Alarms.........................................................................4 13.14.1 High Level Alarms............................................................................................... 4 13.14.2 Tank Overfill Alarms ........................................................................................... 4 Tank Radar Systems .................................................................................................4 Oil Discharge Monitoring and Control Equipment ....................................................4 Portable Hermetic Gauging and Sampling Equipment .............................................5 Transfer Equipment Test and Inspections................................................................5 Valves 5 13.19.1 Sea Suction and Overboard Valves ....................................................................... 6 13.19.2 Pipelines ............................................................................................................ 6 Flexible Hoses ...........................................................................................................6 Calibration ................................................................................................................6



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13.21.1 General ............................................................................................................. 6 13.21.2 Calibration method ............................................................................................. 7 13.21.3 Documentation................................................................................................... 7 13.21.4 Designation of measuring and testing devices ....................................................... 7 13.21.5 Defective measuring and test devices................................................................... 7

14.

DOCUMENTATION AND CARGO CALCULATION ...................................... 1

14.1 14.2 14.3 14.4 14.5

14.6 14.7 14.8 14.9 14.10 14.11 14.12

14.13 14.14 14.15 14.16

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 General......................................................................................................................1 ASTM Tables..............................................................................................................2 Density, Relative Density and API ............................................................................2 14.5.1 Density .............................................................................................................. 2 14.5.2 Relative Density 15/4.......................................................................................... 2 14.5.3 Relative Density 60/60 (SG) ................................................................................ 3 Volume Reduction to Standard Temperature ...........................................................3 Ullage Reports ..........................................................................................................3 Ship’s Experience Factor (SEF or VEF)......................................................................3 (“Rough”) Port/Cargo Log........................................................................................4 Notice of Readiness (nor) .........................................................................................4 Bill of Lading, B/L .....................................................................................................5 Letters of Protest ......................................................................................................6 14.12.1 Difference Protest............................................................................................... 6 14.12.2 Deadfreight Protest............................................................................................. 7 14.12.3 Temperature Protest........................................................................................... 7 14.12.4 Low loading or discharging rate protest. ............................................................... 7 14.12.5 Exceeding the maximum agreed quantity ............................................................. 8 Statement of Facts....................................................................................................8 Dry Tank Certificate ..................................................................................................9 Other Documents......................................................................................................9 Departure Telex/Fax/Email......................................................................................9

15.

MAINTENANCE ROUTINES ..................................................................... 1

16.

CARGO COMPATABILITY........................................................................ 1

15.1 15.2 15.3 16.1 16.2 16.3 16.4

Reference Publications .............................................................................................1 Company Forms ........................................................................................................1 Maintenance Routines ..............................................................................................1 Reference Publications .............................................................................................1 Explanation of Cargo Compatibility Chart ................................................................1 Using the Compatability Chart..................................................................................1 Compatability Chart..................................................................................................2

CHEMICAL TANKER MANUAL SECTION 1 - GENERAL

1.

GENERAL

1.1

DEFINITIONS


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VMS/CHM/01 01 1 of 11

♦ Acute Toxic Effect

The effect on humans of a single exposure of short duration to high concentrations of a toxic compound or toxic vapour (see also Chronic Toxic Effect).

♦ Alcohol Resistant Foam (Alcohol-type foam)

A multi-purpose fire fighting foam effective against many water soluble cargoes. This is the most commonly used type of fire fighting foam on chemical tankers.

♦ Anaesthesia

A total loss of feeling and consciousness, or the loss of power or feeling over a limited area of skin.

♦ Anaesthetics

Chemicals which produce anaesthesia.

♦ Aqueous

Indicating that the compound is in solution in water.

♦ Asphyxia

The condition arising when the blood is deprived of an adequate supply of oxygen, so that loss of consciousness may follow.

♦ Asphyxiant

A gas or vapour, which may or may not have toxic properties, which when present in sufficient concentrations excludes oxygen and leads to asphyxia.

♦ Audit

A method of checking that procedures (as written down) are being followed, and that any amendments required have been carried out to maintain a quality service.

♦ Auto-ignition Temperature (Autogenous Ignition Temperature; Ignition Temperature)

The lowest temperature to which a solid, liquid or gas requires to be raised to cause self-sustaining combustion without initiation by a spark or flame or other source of ignition (see also Flash Point).

♦ BCH Code

The IMO Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk.

♦ Catalyst

A substance that starts or changes the rate of a reaction without being itself chemically changed. A catalyst which reduces the rate of a reaction is known as a negative catalyst.



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♦ Certificate of Fitness (COF)

A certificate issued by the flag administration confirming that the structure, equipment, fittings, arrangements and materials used in the construction of a chemical tanker are in compliance with the relevant IMO Chemical Codes. Such certification may be issued on behalf of the administration by approved classification societies.

♦ Chemical Absorption Detector (Gas Absorption Detector)

An instrument used for the detection of vapours, which works on the principal of a reaction between a vapour and a chemical agent in the apparatus; either the vapour discolours the agent or the agent dissolves some of the vapour.

♦ Chronic Toxic Effect

The cumulative effect on humans of prolonged exposures to low concentrations of a toxic compound or toxic vapour, or of intermittent exposures to higher concentrations (see also Acute Toxic Effect).

♦ Client

The Company or individual to whom V. Ships is providing a service (i.e. the Purchaser of the Service).

♦ Combustible (Flammable)

Capable of being ignited and of burning. For the purpose of this manual the terms combustible and flammable are synonymous.

Combustible Gas Indicator (Explosimeter)

An instrument for detecting a combustible gas/air mixture, usually measuring its concentration in terms of the Lower Flammable Limit (LFL).

♦ Controlled Copy

A copy of the manual or procedures which will be issued for working to, and will be updated with all the modifications, corrective actions and revisions of the procedure.

♦ Corrective Action

Actions taken to correct non-compliances.

♦ Corrosive Liquids

Liquids which can corrode normal constructional materials at an excessive rate. Usually they can also cause serious damage to human tissues and eyes.

♦ Crew Manning Office

Refers to the Company office, which supplies the ships staff to the relevant management office for the managed vessel.

♦ Data Sheet (Cargo Information Sheet)

A document, in accordance with the IMO Codes and usually from the manufacturer of the cargo, that contains necessary information about the properties of the chemical for it’s safe carriage as cargo. (Also MSDS – Material Safety Data Sheet)

♦ Density

Mass per unit volume, measured in a vacuum.

♦ DTF

Document Transmittal Form.



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VMS/CHM/01 01 3 of 11

♦ Endothermic

A process which is accompanied by absorption of heat.

♦ Exothermic

A process which is accompanied by evolution of heat.

♦ Explosion Proof Equipment / Flame Proof Equipment

Equipment or apparatus which will withstand, without damage and in accordance with its prescribed rating, any explosion of a prescribed flammable gas to which it may be subjected under practical operating conditions, and which will prevent the transmission of flame to the surrounding atmosphere.

♦ Filling Ratio

That volume of a tank, expressed as a percentage of the total volume, which can be safely filled by liquid when allowing for the possible expansion of the liquid.

♦ Flame Arrester

A device used to arrest the passage of flame in a pipeline.

♦ Flame Screen (Gauze Screen)

A portable or fitted device incorporating one or more corrosion resistant wire woven fabrics of very small mesh used for preventing sparks from entering a tank or vent opening. For a short period of time a flame screen will prevent the passage of flame, yet permit the passage of gas.

♦ Flammable (Combustible)

Capable of being ignited and of burning. For the purpose of this manual the terms combustible and flammable are synonymous.

♦ Flammable Limits (Explosive Limits)

The minimum and maximum concentrations of vapour in air which form flammable (explosive) mixtures are known as the lower flammable limit (LFL) and upper flammable limit (UFL) respectively. These terms are synonymous with lower explosive limit (LEL) and upper explosive limit (UEL) respectively.

♦ Flammable Range

The range of flammable vapour concentrations in air between the lower and upper flammable limits. Mixtures within this range are capable of being ignited and of burning.

♦ Flash Point

The lowest temperature at which a liquid gives off sufficient vapour to be ignited. This temperature is determined by laboratory testing in a prescribed apparatus (see also Autoignition Temperature).

♦ He

The use of the term “he” is to be interpreted as meaning “he” or “she”.

♦ IBC Code

The IMO International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk.

♦ IMO

International Maritime Organisation.

♦ Incendive Spark

A spark of sufficient temperature and energy to ignite a flammable atmosphere.



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♦ Inhibitor

A substance used to prevent or retard cargo deterioration or a potentially hazardous chemical self-reaction, eg., polymerisation.

♦ ISM Code

International Safety Management Code.

♦ ISO 9001:2000

International Standards Organisation Standards for Quality Systems in a Service Industry.

♦ ISO 14001

International Standards Organisation environmental and emissions standard.

♦ ISPS Code

International Ships and Port Facility Security Code.

♦ LR

Lloyds Register

♦ Management Office

Refers to the company office, which manages the relevant vessel.

♦ Manual

A compilation of VMS procedures, instructions and information within a V. Ships identified Binder.

♦ Miscibility

The ability of a liquid or gas to dissolve uniformly in another liquid or gas.

♦ Narcosis

A condition of profound insensibility, resembling sleep, in which the unconscious person can only be roused with great difficulty but is not entirely indifferent to sensory stimuli.

♦ Non-compliance

A deviation from a procedure i.e. a part of the procedure part of which is not being operated accordingly.

♦ Odour Threshold

The smallest concentration of gas or vapour, expressed in parts per million (ppm) by volume in air, that most people can detect by smell.

♦ Oxidising Agent

An element or compound that is capable of adding oxygen or removing hydrogen; or one that is capable of taking one or more electrons from an atom or group of atoms (the opposite of a Reducing Agent).

♦ Padding

Filling and maintaining the cargo tank and associated piping system with an inert gas, other gas or vapour, or liquid, in order to separate the cargo from air.

♦ Peroxides

Compounds formed by the chemical combination of cargo liquid or vapour with atmospheric oxygen, or oxygen from another source. These compounds may in some cases be highly reactive or unstable and constitute a potential hazard.

♦ P + I Club

Protection and Indemnity Club



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VMS/CHM/01 01 5 of 11

♦ Polymerisation

The phenomenon whereby the molecules of a particular compound link together into a larger unit called a polymer. A great deal of heat may be evolved when this occurs. Polymerisation may occur spontaneously with no outside influence, or it may occur if the compound is heated or if a catalyst or impurity is added. Polymerisation may, under some circumstances, be dangerous but may be delayed or controlled by the addition of inhibitors.

♦ Pour Point

The lowest temperature at which a liquid will remain fluid.

♦ Putrefaction

The natural decomposition, over time, of animal or vegetable oils, accompanied by offensive smells.

♦ Reducing Agent

An element or compound that is capable of removing oxygen, or adding hydrogen; or one that is capable of giving one or more electrons to an atom or group of atoms.

♦ Reid Vapour Pressure (RVP)

The vapour pressure of a liquid determined by laboratory testing in a standard manner in the Reid Apparatus at a standard temperature of 100 Deg F (37.8 Deg C) expressed in pounds per square inch absolute, and commonly written RVP lb’.

♦ Relative Vapour Density

The relative weight of the vapour compared with the weight of an equal column of air at standard conditions of temperature and pressure.

♦ Self-reaction

The tendency of a chemical to react with itself, usually resulting in polymerisation or decomposition. Self-reaction may be promoted by contamination with small amounts of other materials.

♦ “SEP”

Refers to Safety and Environmental Protection.

♦ S.M.P.E.P.

Shipboard Marine Pollution Emergency Plan.

♦ Solubility

The ability of one substance (solid, liquid or gas) to blend uniformly with another. Solubility is usually understood as the maximum weight of substance which will dissolve in water in the presence of undissolved substances.

♦ S.O.P.E.P.

Shipboard Oil Pollution Emergency Plan.

♦ Systemic Toxic Effect

The effect of a substance or its vapour on those parts of the human body with which it is not in contact.

♦ “The Company”

Refers to V. Ships.


1.2


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VMS/CHM/01 01 6 of 11

♦ “The Group”

Refers to the group of V Ships Divisions i.e Ship Management Division Leisure Division Commercial Division

♦ Threshold Limit Value (TLV) (Short Term Exposure Limit)

The time weighted average (TWA) concentration of a substance to which it is believed workers may be repeatedly exposed, for a normal 8 hour working day and 40 hour working week, day after day, without adverse effect. It may be supplemented by other limits.

♦ Toxic

Poisonous ie., causing bodily harm that may be severe (see also Acute Toxic Effect and Chronic Toxic Effect).

♦ UTI

Ullage, Temperature and Interface detector instrument.

♦ Vapour Pressure

The pressure exerted by the vapour above the liquid, at a given temperature.

♦ Vendor/Supplier

A Company or individual who is supplying Subcontractor material or a service to V Ships.

♦ Viscosity

The property of a liquid, which determines its resistance to flow.

♦ VMS

V Ships Management System

♦ Volatile Liquid

A liquid, which evaporates readily at ambient temperatures.

♦ V. Ships

Refers to the group of V Ships Companies.

INTRODUCTION This Manual is issued in accordance with the Company's VMS and contains specific instructions etc. based on V Ships operating experience. The subject matter was selected where the Company considered that emphasis had to be placed on the relevant operational procedures, precautions, instructions etc. The following procedures are to be adhered to in order to achieve safe and effective Company Operating Standards. Adoptions of other unapproved procedures may lead to a breach of the Company's Instructions and could result in disciplinary action being taken against the individual. This manual is controlled under the Company's VMS and will be revised as required. Copying of the relevant sections of this manual is permitted, for operational purposes, but all copies are to be considered as “uncontrolled” documents, and must be destroyed following use. Revisions will be issued as required and the date of insertion of the revised section is to be recorded with the Manager or Master’s initials. The pages of the section rendered obsolete, are to be immediately destroyed.



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VMS/CHM/01 01 7 of 11

An updated CD Rom will be issued in conjunction with the abovementioned revision and is to be entered into the relevant on board computer on receipt. The obsolete CD Rom is to be immediately destroyed. When referencing the VMS manuals, the Document and Revision numbers must always be used. It is the Master's responsibility to ensure that any amendments received, are inserted within this manual and the appropriate electronic entries made. Any procedure which he considers cannot be adhered to, must be brought to the Company’s attention. This manual remains the property of the Company and in the event of the ship leaving the Company's Management, all copies of this manual and the relevant CD Rom are to be destroyed, unless instructions are received to the contrary.

1.3

DEPARTURE FROM THESE PROCEDURES The first consideration of the Master and every Officer must be the safety of the lives on board and that of the ship, her cargo and the environment. Where a deviation from the Company's Instructions/procedures is found to be necessary the Master will report this to the Company at the first opportunity.

1.4

VMS MANUALS Reference is to be made to the following VMS system “core” manuals which are issued to all types of vessels:

• • • • •

V Ships Management Manual Fleet Operating Manual Crew Manual Safety and Environmental Manual Ship Forms Manual

VMS/VMM/01 VMS/FOM/01 VMS/CRW/01 VMS/SEM/01 VMS/FMS/01

* The V Ships Management Manual is the umbrella manual of the VMS, and its purpose is to describe the structure by which the VMS is implemented and maintained. It relates to all the requirements of the applicable standards and the IMO ISM code and ISO 14001.

1.5

CHECKLISTS The Company recognises the importance of operational checklists to assist the Master, Chief Engineer and all Officers in the routine operation of the ships concerned. The Operations checklists fully embrace the Company's Instructions, Procedures and Documentation for the safe technical operation of the vessel, the safety of the crew, the cargo and the environment. These checklists are to be used when required, and whenever completed, a log entry is to be made which must include the checklist number, description and completing officer’s signature. It is emphasised that the checklists are to assist the relevant Officer, and do not detract from his responsibility towards the safety of the vessel, her crew, her cargo and the environment.

1.6

REFERENCE PUBLICATIONS The Company recognises the importance of certain reference publications and these are listed here. These publications are to be made available to all on board.



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VMS/CHM/01 01 8 of 11

The recommendations of these publications are to be adopted as standard procedures, and are to be read in conjunction with this manual. Each publication is to be given a Company Reference Number, and is to be kept in the recommended location. Reference publications will be updated through the Company’s Chart and Publication New Edition scheme. Superseded publications are to be removed and destroyed. ICS Tanker Safety Guide (Chemicals) IBC Code and BCH Code Regulations for the Prevention of Pollution (MARPOL 73/78 Consolidated Edition) as amended SOLAS Medical First Aid Guide for Use in Accidents involving Dangerous Goods (IMDG Code MFAG) OCIMF Guidelines for the Control of Drugs and Alcohol Onboard Ship International Safety Guide for Oil Tankers and Terminals (ISGOTT) ICS Guide to Helicopter / Ship Operations International Regulations for Preventing Collisions at Sea IMO Ship’s Routing International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW 95) International Code of Signals OCIMF/ICS Ship to Ship Transfer Guide (Petroleum) OCIMF Effective Mooring OCIMF Mooring Equipment Guidelines WHO International Medical Guide for Ships International Safety Management Code IMO IAMSAR Vol 3 ICS Bridge Procedures Guide OCIMF/ICS Clean Seas Guide for Oil Tankers Nautical Institute Bridge Team Management

1.7

COMPANY FORMS The Company requires certain records and documentation to be maintained both on board the ship and within the Management Office.



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VMS/CHM/01 01 9 of 11

References to the Company Forms are contained within the Ship Forms Manual VMS/FMS/01.

1.8

ABBREVIATIONS

API

American Petroleum Institute (USA).

ASTM

American Society for Testing and Materials (USA).

BCH Code

Code for Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk for Ships built before 1 July 1986.

CBT

Clean Ballast Tanks

CFR

Code of Federal Regulations (USA).

CHRIS Code

Chemical Hazards Response Information System (USCG)

COA

Contract of Affreightment

COF

Certificate of Fitness

EDP

Early Departure Procedure.

EmS

Emergency Schedules (to MFAG)

ESD Valve

Emergency Shutdown Valve

HLA

High Level Alarm

IBC Code

International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk.

ICS

International Chamber of Shipping.

IEC

International Electrotechnical Commission

IG

Inert Gas.

ILO

International Labour organisation

IMDG Code

International Maritime Dangerous Goods Code

IMGS

International Medical Guide for Ships

IP

Institute of Petroleum (London).

IMO

International Maritime Organisation

ISGOTT

International Safety Guide for Oil Tankers and Terminals

ISM Code

International Management Code for the Safe Operation of Ships and for Pollution Prevention (the International Safety Management (ISM) Code).



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VMS/CHM/01 01 10 of 11

IWRC

Independent Wire Rope Core.

LEL (LFL)

Lower Explosive (or Flammable) Limit

MAC

Maximum Allowable Concentration of a vapour

MARPOL

International Convention for the Prevention of Marine Pollution from Ships

MBL

Minimum Breaking Load.

MFAG

Medical First Aid Guide for Use in Accidents Involving Dangerous Goods (Supplement to IMDG Code)

MSDS

Material Safety Data Sheet.

NLS

Noxious Liquid Substances.

NOS

Noxious Other Substances.

OBQ

On Board Quantity (cargo before loading).

OCIMF

Oil Companies International Marine Forum.

OPA-90

Oil Pollution Act 1990 (USA).

P&A Manual

Procedures and Arrangements Manual

PEL

Permissible Exposure Limit (Toxicity).

PPE

Personal Protective Equipment

PPM

Parts per Million.

PSA

Pressure Swing Adsorption

PTT

Permanganate Time Test

P/V Valve

Pressure / Vacuum valve

ROB

Remaining On Board (cargo after discharging).

RVP

Reid Vapour Pressure

SBM

Single Buoy Mooring.

SBT

Segregated Ballast Tank.

SCBA

Self-contained compressed air breathing apparatus

SEF (VEF)

Ship’s (Vessel’s) Experience Factor.

SMPEP

Shipboard Marine Pollution Emergency Plan

SOLAS

International Convention for the Safety of Life at Sea

SOPEP

Shipboard Oil Pollution Emergency Plan.


1.9


SPM

Single Point Mooring.

STEL

Short Term Exposure Limit (Toxicity).

STS

Ship to Ship transfer.

TLV

Threshold Limit Value (Toxicity).

TWA

Time Weighted Average (Toxicity).

UEL (UFL)

Upper Explosive (or Flammable) Limit.

VEC

Vapour Emission Control.

VOC

Volatile Organic Compounds

VRP

Vessel Response Plan (USA OPA-90).

VRU

Vapour Recovery Unit

WHO

World Health Organisation

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VMS/CHM/01 01 11 of 11

APPLICABILITY • •

The terms “vessel” or “ship” used throughout this document refer to all seagoing vessels involved in the carriage of liquid dangerous cargoes in bulk. “Dangerous cargoes” are those petroleum products with any flash point listed in the Marpol Convention 73/78 Annex I as amended, noxious and chemical liquid substances listed in Appendix II and III of Marpol Convention 73/78 Annex II, as amended.

CHEMICAL TANKER MANUAL SECTION 2 - RESPONSIBILITIES

2.

RESPONSIBILITIES

2.1

GENERAL


: : :


In the operation of any vessel it is essential that good-co-operation exists between all ranks on board. The Job Descriptions contained in the Crew Manual concerning cargo operations to be expanded as follows:

2.2

MASTER The Master is responsible for: • • • • • • • • • • •

2.3

Ensuring that the voyage orders are fully understood and complied with. Advising the Chief Engineer and Chief Officer of the relevant details of intended voyage. Providing the Company and Charterers with accurate information regarding the cargo operations. Advising the Company when instructions cannot be complied with or he is unsure of the intended voyage instructions. Supervision of cargo system and spaces preparation including cleaning requirements. The Checking and verification of cargo plans prepared by Chief Officer. The Supervision of all cargo and ballast operations on board. The monitoring of the vessel’s stress and stability throughout the cargo and ballast operations and during the voyage to ensure that they remain within the required limits. The Completion, checking and signing as applicable of cargo documents. Ensuring that Hours of Work are in accordance with STCW regulations. Ensuring cargo compatibility guides are complied with

CHIEF OFFICER Under the supervision of the Master the Chief Officer is responsible for: • • • • • • • • • • • • • • •

The preparation of the cargo plan in compliance with the voyage orders. The checking of the cargo system to ensure that the intended plan will be followed. The preparation of ship’s cargo system and spaces for intended cargo. The monitoring of all cargo and ballast operations on board and personal supervision of commencement and completion of these operations. Cross referencing cargo compatibility guides. The operation and control of all cargo equipment. Producing his own written standing orders concerning the cargo operations which are to be well understood and signed by each Deck Officer. The monitoring of the vessel’s stress and stability throughout the cargo and ballast operations and during the voyage to ensure that they remain within the required limits. The maintenance of cargo records as required by the Company, Charterers and International regulations. The calculation of the quantity on board and preparation of cargo documentation as required. The checking of all compartments on a daily basis and recording the sounding in the Deck Log Book. Ensuring that empty tanks and void spaces surrounding cargo spaces which contain flammable cargoes are tested for combustible gas as far as practicable on a daily basis, and the results are recorded in the Deck Log Book. For monitoring of toxic gases vapours concentration in ship’s compartments as required. Maintaining the records in conjunction with the Chief Engineer as required. Applying the ballast water management practices and maintaining records.

CHEMICAL TANKER MANUAL SECTION 2 - RESPONSIBILITIES

2.4


: : :


SECOND OFFICER AND THIRD OFFICER The Second and Third Officers are responsible to the Chief Officer for:• • • •

2.5

Assisting in all cargo, ballast and cargo spaces preparation. Monitoring of cargo and ballast operations as instructed by the Chief Officer. Ensuring that a proper deck and security watch is maintained. Ensuring that the vessel remains securely moored at all times.

CHIEF ENGINEER The Chief Engineer is responsible for the maintenance and repair of all cargo and ballast related equipment. He is to assist the Chief Officer in the operation of the cargo-related equipment. He is to keep the Chief Officer advised of any bunker, lubricating oils or sludge transfer, which may affect the ship’s trim, stress and/or stability.

2.6

PUMPMAN He is to assist in cargo operations as required by the Chief Officer.

2.7

RATINGS The Deck Ratings are responsible to the Deck Officers for maintaining a safe deck watch and ensuring that the vessel remains securely moored. They are to assist in cargo operations (inc. tank cleaning, sweeping) as required by the Chief Officer and or Officer on Watch.

CHEMICAL TANKER MANUAL SECTION 3 – SAFETY


3.

SAFETY

3.1

REFERENCE PUBLICATIONS

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VMS/CHM/01 01 1 of 24

The following reference publications are to be read in conjunction with this section:

3.2

Publication

Location

SOLAS - 74 as amended MARPOL – 73/78 as amended BCH / IBC Code International Safety Guide for Oil Tankers and Terminals (ISGOTT) Tanker Safety Guide (Chemicals) Ship to Ship Transfer Guide (Petroleum) Safety in Oil Tankers Safety in Chemical Tankers IMDG Code Supplement to IMDG Code (Including MFAG and Ems) SOPEP Clean Seas Guide for Oil Tankers FOSFA (for Oils, Seeds and Fats) Prevention of Oil Spillage through Cargo Pumproom Sea Valves CHRIS Guide (USCG) MSDS for particular cargo carried

Master Master Master Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer Chief Officer

COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Title

Company Form No SAF05

-

Cold Work Permit

SAF11

-

Enclosed Space Entry Permit

TNK14

-

Pumproom space entry permit

SAF 10

-

Permit to allow small craft alongside

3.3

CHEMICAL HAZARDS

3.3.1

General This section and section 3.4 deal with the properties and hazards of most Chemicals carried in bulk on chemical Tankers. Chemical Tanker operations differ from any other liquid bulk transportation, in that a large number of cargoes of different properties and characteristics and inherent hazards may be carried simultaneously, on a single voyage, and that numerous products may be handled at one berth, typically including both discharge and loading as well as tank cleaning. Transportation of bulk chemicals do not only require special hardware, but also special crew training, both theoretical and



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VMS/CHM/01 01 2 of 24

practical, in order for them to understand the characteristics of the various chemicals and be aware of the potential hazards involved in handling them. This chapter is meant to highlight the most common characteristics and hazards of chemicals transported in bulk, and is a supplement to the ICS Tanker Safety Guide (Chemicals), ISGOTT, CHRIS Guide and specific MSDS supplied by the shippers. 3.3.2

Flammability Vapour given off by a flammable liquid will burn when ignited provided it is mixed with certain proportions of air. If the vapour mixture is too lean or too rich it will not burn. The range in which it will burn is called the flammable range, and the limits are called the lower flammable limits (LFL) and the upper flammable limits (UFL). See definitions carried in Section 1 of this Manual for further details. A flammable vapour also needs Oxygen in order to burn, typically in excess of 11 percent for hydrocarbon vapours. In addition a flammable liquid must be at a temperature high enough to give off sufficient vapour in order to ignite (the Flash Point). For the purpose of safe handling procedures, the flammability characteristics of various products are divided into three broad categories: Flammable cargoes------------ flash point not exceeding 60°C Combustible cargoes-----------flash point exceeding 60°C Non-combustible cargoes------cargoes which have no flash point

3.3.3

Toxicity Toxicity may be described as the ability of a substance to cause damage to living tissue, impairment of the central nervous system, severe illness or, in extreme cases, death when inhaled, ingested, or absorbed by the skin. The amounts required to produce these results vary widely with the nature of the substance and the time of exposure to it. Toxicity is divided into two main groups; “acute” which refers to exposure of a short duration, i.e. a single brief exposure, and the “chronic” toxicity refers to exposure of long duration, i.e. repeated or prolonged exposures. Toxicity is objectively evaluated on the basis of test dosages made on experimental animals under controlled conditions. Prevention from exposures is achieved by a combination of preventing toxic fumes or liquid from contaminating the workplace and the use of Personal Protective Equipment. It shall be noted that a chemical may be both toxic and explosive/flammable. Threshold Limit Value (TLV) TLV refers to the maximum concentration of gases, vapours, mist or sprays to which it is believed that nearly all persons may be repeatedly exposed day after day without adverse effects. TLV is stated as Time Weighted Average (TLV-TWA), Short Term Exposure Limit (TLV-STEL) and Ceiling (TLV-C): usually expressed in parts per million (ppm). Refer to ISGOTT for more details.

3.3.4

Asphyxia Asphyxia can be described as a condition caused by lack of air (oxygen) i.e. suffocation. Any vapour may cause asphyxiation, whether toxic or not. Danger areas are cargo tanks, void spaces, double



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VMS/CHM/01 01 3 of 24

bottoms, pump rooms, peaks etc. and before entering these spaces The Company’s Enclosed Space Entry procedures must be observed. 3.3.5

Anaesthesia Certain vapours have an anaesthetic effect and may cause loss of consciousness due to its effect on the nervous system. Anaesthetic vapours could be both toxic or non toxic.

3.3.6

Reactivity Chemicals may react in a number of ways; with water, with itself, with air, with other chemicals or with other materials. Self-reaction The most common form of self-reaction is polymerisation. Polymerisation may be a slow natural process which only degrades the product without posing any safety hazards, or it may be a rapid exothermic reaction with a large amount of heat build-up and gases evolved. Such a reaction is called a run-off polymerisation and poses a serious danger to both the ship and its personnel. Products that are self-reactive are inhibited with a stabiliser to prevent self-reaction. The action to be taken in case of a polymerisation situation should be covered by the ship’s emergency/contingency plan. Reaction with water Certain cargoes react with water, most noticeable the isocyanates, in a way that could pose a danger to both the ship and it’s personnel. These cargoes are carried under inert condition, see chapter 9 in the IBC code. Other cargoes reacts with water in a slow way that poses no safety hazards, but the reaction could cause chemicals that may damage equipment and/or tank materials. Reaction with air Certain cargoes may react with air to form unstable oxygen compounds (peroxides) which, when allowed to build up, could cause an explosion. Such cargoes are either inhibited by an anti-oxidant and/or carried under inert condition. Reaction with other cargoes Certain cargoes react dangerously with one another. Such cargoes should be stowed away from each other (not adjacent) and prevented from mixing by using separate cargo and vent lines. The master must ensure that cargoes stowed adjacent to each other are compatible, and should consult the USCG CHRIS compatibility guide (Section 16) prior to loading. Reaction with other materials The materials of construction must be compatible with the cargo to be carried. Some materials may react with the product and trigger a self- reaction within the product, some alloys will react in a non hazardous way, but render the product unusable or in case of an edible product, inedible. See the IBC code.


3.3.7


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Corrositivity Acids, anhydrides and alkalis are among the most common carried corrosive substances. They can rapidly destroy human tissue and cause irreparable damage. They can also corrode normal construction materials, and create a safety hazard to the ship. Acids in particular react with most metals evolving hydrogen gas, which is highly flammable. As to suitable materials of construction see IBC code. Handling of these substances should only be done wearing suitable Personal Protective Equipment.

3.3.8

Putrefaction Most animal and vegetable oils undergo decomposition, this process, known as putrefaction, generates obnoxious and toxic vapours and deplete the oxygen in the tank. Tanks that have contained such product must be properly ventilated and the atmosphere tested prior to tank entry. This is especially important prior sending personnel into the tank for sweeping purposes. Strict compliance with the tank entry procedures required by VMS/SEM/01 to apply.

3.4

PHYSICAL PROPERTIES OF CHEMICALS

3.4.1

Specific Gravity (Density) Tanks on a Chemical Tanker are normally designed to load cargoes of a higher specific gravity than an oil tanker. Very often the design strength differs between groups of tanks on the same ship. The information with regards to tank strengthening is normally found on the Certificate of Fitness, and the master must be familiar with this lay-out and the restrictions that may be imposed on loading high gravity cargoes. Especially important is the risk of slack loading a tank as this can cause excessive sloshing in the tank that may cause damage to the tank structure and/or its equipment. Equally important is the danger of exceeding the tank’s design weight capacity.

3.4.2

Flash Point The flash point of a liquid is the lowest temperature at which the liquid will give off vapour to form a flammable gas mixture with air, near the surface of the liquid.

3.4.3

Auto Ignition Temperature The auto ignition temperature of a solid, liquid, or gas is the lowest temperature at which it requires to be raised to support self initiated combustion.

3.4.4

Flammable / Explosive Limits The flammable (explosive limits) are the minimum and maximum concentrations of flammable gas or vapour in air between which ignition can occur. The Minimum vapour concentration is known as: The Lower Flammable Limit The Lower Explosive Limit

LFL LEL



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VMS/CHM/01 01 5 of 24

The maximum vapour concentration is know as: The Upper Flammable Limit UFL The Upper Explosive Limit UEL 3.4.5

Vapour pressure/Boiling point Every liquid exerts a certain pressure at any given temperature called the vapour pressure. The liquid will boil when the vapour pressure equals the external atmospheric pressure. In a closed ship tank, however, the liquid will boil when the vapour pressure equals the external vapour pressure plus the pressure setting of the P/V valve. The tanks and vent systems are designed to withstand this pressure, plus the hydrostatic pressure of the cargo. Unless specially designed, the Master must not accept cargoes for loading that exceed the normal atmospheric pressure at 37.8 degrees centigrade. The higher the vapour pressure the more vapours will be released. A fact that requires special personal protection equipment, especially with toxic cargoes.

3.4.6

Freezing point Most liquids have a defined freezing point, sometimes described as the melting point. Some products, like lube oil additives, vegetable and animal oils, polyoils etc do not have a defined freezing point, but rather a freezing (melting) range or non at all. The product’s viscosity is instead used as a measurement for the products liquidity or handling characteristics. Products with a freezing point higher than the outside temperature in which the ship is trading, will need to be heated in order to remain liquid. Ship’s structure and equipment normally have limitations on high heat. Exceeding this limitation could damage the tanks or their structure. High heat will also reduce steel strength, and the risk of cracking will increase. Caution should be exercised when carry high heat products as non-insulated lines and vents may freeze and clog the systems. Not insulated cargo lines used for high heat products pose a safety hazard as they may cause severe burns if touched.

3.4.7

Pour Point The pour point of a liquid is the lowest temperature at which the liquid will flow. It should be noted that oil with thixotropic properties (the properties of showing a temporary reduction in viscosity when shaken or stirred) can be pumped at temperatures well below its pour point, but at very restricted rates.

3.4.8

Viscosity Viscosity is a measure of a liquid’s ability to flow and is usually determined by measuring the time required for a fixed volume to flow under gravity through a thin tube at a fixed temperature. As the temperature of the liquid increases its viscosity decreases and therefore it flows more readily. It can also be described as a measure of the internal friction of a liquid. The distinction between viscosity and pour point should be made clear. Oil ceases to flow below its pour point temperature when the wax content solidifies. A viscosity measurement of a liquid depends upon the internal resistance of the liquid to flow. For a simple liquid this internal resistance varies with the temperature in a predictable and regular way. However, when an oil approaches its pour point the rate at which viscosity increases as temperature falls accelerates until sufficient wax has precipitated to solidify the product.



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Viscosity is important as regards the pumpability of a product. Centrifugal and deepwell pumps are acceptable for the majority of cargoes but high-viscosity products such as bitumen or molasses are more suited for pumping with positive displacement pumps. 3.4.9

Cubic expansion All liquids will expand as temperature rises, or contract when temperature decreases. Sufficient space must be allocated in the tank to facilitate any cubic expansion or contraction expected during the voyage. Vent line systems must be checked for operation at regular intervals, as malfunction could cause structural damages because of changes in the liquid’s volume.

3.4.10 Vapour density Vapour density is expressed relative to density of air. Many chemical cargo vapours are heavier than air, caution must be exercised during loading and any other cargo operation, as vapour concentrations may accumulate and be trapped in certain deck areas. (If cargo tanks are incorrectly cleaned vapour may remain in the bottom of the tank). 3.4.11 Solubility Solubility is expressed in many different ways; yes, no, slight, as a percentage or totally and in this connection only with water. Most non-soluble chemicals are lighter than water and will float on top, others like the chlorinated solvents are heavier and will sink to the bottom. This latter condition may cause a safety risk in drip trays and even in cargo tanks where they may be trapped under water in pump wells, and pose a danger even if the tank atmosphere is tested safe for entry. 3.4.12 Colour Colour is the comparison between a sample of product and standard colours measured under closely controlled conditions. The colour of clean products is one of the more common causes of cargo rejection or downgrading. This is generally caused by loading a light-coloured product without adequate preparation into a tank that last carried a darker product. Most of the lube oils and whitewater products show quite readily the traces of prior darker lube oils or residual products, and because of this trait, it is most important that the tank cleaning instructions are closely followed. 3.4.13 Electrostatic charging Certain cargoes are so called static accumulators, and may accumulate enough static electricity to release a spark that could ignite a flammable tank atmosphere. See static electricity.

3.5

GENERAL PRECAUTIONS

3.5.1

General This section covers general precautions that should be observed irrespective of cargoes carried. Additional precautions for specific cargoes are dealt with in other chapters and should also be incorporated in the ship’s cargo handling procedures. These general precautions should be observed



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VMS/CHM/01 01 7 of 24

at all times, both in port and at sea as applicable. Ports and terminals may have additional and different precautions and it is the Master’s responsibility to ensure that local regulations are understood and observed. 3.5.2

Cargo Information The IMO chemical codes as well as Marpol Annex 2 require that certain information must available on board prior to loading, reference is made to chapter 16 in the IBC code and chapter 5 in the BCH code. It is the Master’s responsibility to ensure that the necessary information, including Material Safety Data Sheets are on board for each cargo, and available to all personnel onboard and involved in cargo handling. Loading should not commence before the Master is satisfied that the necessary information for safe handling of the cargo is available.

3.5.3

Personnel protection All tankers designated for carriage of dangerous chemicals in bulk should have on board suitable protective equipment and clothing for the protection of crew involved in cargo handling and tank cleaning operations. The types and quantities of protective equipment as well as additional safety equipment should be in a strict compliance with requirements of IBC/BCH Code. All ships carrying dangerous cargoes should have on board medical first-aid equipment, including oxygen resuscitation equipment and antidotes for cargo carried in compliance with recommendations listed in IMO -–MFAG (Medical First Aid Guide) and WHO – IMGS (International Medical Guide for Ships).

3.5.4

Moorings The consequences of a chemical tanker ranging along or breaking away from a berth could be disastrous, especially during cargo transfer that may include multiple different chemicals. Correct and sufficient mooring is therefore of the utmost importance. Mooring requirements and arrangements are usually determined by the location and the lay-out of the terminals, supplemented by recommendations from the pilot. Chemical terminals are often located in tidal areas or rivers, with other ships passing at close distances, making proper mooring and constant checking and adjustment a major safety issue. The Master should ensure that sufficient personnel are available for mooring adjustments.

3.5.5

Emergency towing-off wires (fire wires) Emergency towing-off wires are mandatory when alongside a berth in most ports. The wires should be positioned fore and aft on the off-berth side, properly secured and ready for use without adjustment. There may be various methods in use for rigging emergency wires in different ports.

3.5.6

Means of Access and Escape (Gangways or Accommodation Ladders etc.) Personnel should only use the designated means of access between ship and shore or between ship and ship.



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VMS/CHM/01 01 8 of 24

When a ship is berthed, at anchor, or alongside another ship, the means of access should be placed as to be convenient for supervision and as far as possible from the cargo manifold area. Means of access should be as close to the living accommodation as possible. Gangways or other means of access are to be properly secured and a safety net fitted. Life buoy and line to be available at the access point. Emergency means of disembarkation must also be considered (i.e. such as lifeboat etc.) During darkness the means of access and the surrounding areas must be adequately illuminated. 3.5.7

Unauthorised Persons Persons who have no legitimate business on board, or who do not possess permission to be there, should be refused access. The Master should provide the terminal with a crew list and advise the terminal that only personnel that can document a legitimate business with the ship should be allowed onto the ship. Compliance with the ISPS Code and Ship Security Plan is mandatory.

3.5.8

Persons Smoking or Intoxicated Watch standing personnel must ensure that no one who is smoking approaches or boards the vessel. Smoking on board must only take place in designated smoking areas. The company policy on drugs and alcohol must be strictly enforced.

3.5.9

Permanent Notices Permanent notices complying with international standards should be displayed in conspicuous spaces onboard, indicating prohibited smoking and use of naked lights areas. Enclosed areas that need to be ventilated prior to entering must also be marked.



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3.5.10 Temporary Notices and signals On arrival at a terminal, and throughout the vessel’s stay alongside, temporary notices are to be displayed at the point of access or other conspicuous spaces, in the English language, to indicate the following:

WARNING ! NO NAKED LIGHTS NO SMOKING NO UNAUTHORISED PERSONS SWITCH OFF MOBILE PHONES In addition, when hazardous chemicals are being handled a further notice should be displayed stating:

WARNING ! HAZARDOUS CHEMICALS Local national or port regulations may require additional notices which the Master must ensure are complied with. Dangerous cargo lights and international code flag are to be displayed as appropriate. 3.5.11 Craft Alongside When barges or another Chemical tanker are alongside engaged in cargo operations the precautions mentioned in the checklists and work permits for craft alongside must be observed. Unauthorised craft should be prohibited to come alongside. Tugs or mooring boats must observe the no smoking rule when alongside. 3.5.12 Wind conditions Most chemical vapours are heavier than air and vapours that may be released during loading, gasfreeing or accidental spills will sink and may concentrate on lower deck areas, especially in conditions of little or no wind. Strong winds may create vapour pockets on the lee side of deckhouses or other structures. 3.5.13 Electrical Storms During electrical storms in the immediate vicinity of the ship, all cargo operations, including ballasting, gas-freeing and tank cleaning that involves flammable cargoes must be stopped.



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3.5.14 Cold weather During freezing weather conditions precautions must be taken to prevent equipment and systems from freezing. Such equipment and systems include pneumatic valves and control system, fire lines and hydrants, steam driven equipment, cargo heating systems, pressure/vacuum valves, etc. Special attention must be paid to emergency showers and eye-wash stations. A Risk Assessment should be conducted when it becomes known that the vessel is required to operate in freezing conditions. 3.5.15 Openings in deckhouses and superstructures Regulations require that portholes in the superstructure within a certain distance of the cargo deck must be fixed shut. These design features must not be modified in any way. All doors, portholes and other openings should be kept closed during cargo operations. Doors that need to be closed when in port must be marked accordingly. Mechanical ventilation should be stopped and air conditioning units operated on closed cycle or stopped in situations where toxic or flammable vapours may enter the accommodation. 3.5.16 Engine Room Equipment Boiler tubes, uptakes, exhaust manifolds and combustion equipment must be maintained in good condition as a precaution against funnel fires and sparks. In case of a funnel fire, or if sparks are emitted from the funnel, cargo operations involving flammable products should be stopped, and at sea, the course may be altered to prevent sparks falling onto the tank deck. 3.5.17 Excluding Vapour from Machinery Spaces Care should be taken to ensure that flammable or toxic cargo vapour does not enter the engine room spaces. Special attention should be paid to engine room equipment connected to the cargo deck area. In case of an accident or an emergency that could give rise to a situation where toxic or flammable vapours are likely to enter the engine room spaces, consideration should be given to its possible effect on personnel and/or equipment and necessary preventive actions should be taken. 3.5.18 Enclosed Spaces Enclosed spaces like ballast tanks, cofferdams etc in the cargo area may contain flammable or toxic vapours or lack sufficient oxygen and must not be entered without permission from the Master and only if proper ventilation is provided. The Master is responsible for ensuring that the proper Enclosed Space Entry procedures are understood and adhered to. A list of spaces deemed to required Enclosed Space Entry procedures is to be posted up for all crew to note. 3.5.19 Ship’s Readiness to move At all times during discharge, loading and ballasting operations, alongside berth or at anchorage, the ship should be ready for departure at short notice in the event of an emergency. The ship’s boilers,



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main engine, steering gear, mooring equipment and other essential equipment should be kept ready to permit the ship to move from the berth or anchorage at short notice in accordance with terminal and port regulations. Repairs and other work that may immobilise the ship should not be undertaken at a berth without the prior written agreement of the terminal. It may also be necessary to obtain permission from the local port authority before carrying out such work. 3.5.20 Pollution Prevention It is the responsibility of the Master or the ones he delegate to be in charge of cargo operations, including bunkers, to know the applicable international and local pollution prevention regulations and to ensure that they are not violated. Exercises should be held to train personnel in accordance with the Vessel Response Plan and/or the Shipboard Oil Pollution Emergency Response Plan. The Master should ensure that both local and international regulations pertaining to the discharge of ballast water are complied with (See section 12). 3.5.21 Tank-cleaning/gas-freeing Tank cleaning and gas freeing are operations that are frequently carried out on a chemical tanker. The numerous different products involved, often toxic, corrosive or both, may expose the personnel involved to hazardous fumes or liquid, and it is the Master’s responsibility to ensure that the personnel involved are properly trained and understand the hazards involved and take necessary precautions, including use of personal protective equipment (PPE). (See sections 9/11). 3.5.22 Tank-cleaning Chemicals Tank cleaning chemicals used on a chemical tanker may be corrosive, skin sensitive or toxic. When heated they may give off irritating fumes. Personnel handling these chemicals must be familiar with the product MSDS and wear the necessary personal protective equipment (PPE). 3.5.23 Communication Equipment The use of medium or high frequency main radio transmission equipment is prohibited in port and during ship to ship cargo transfers. Aerials must be disconnected and earthed. Usually this does not apply to, satellite equipment and permanently correctly installed VHF equipment, however, Masters must be aware of local/national restrictions. Persons boarding the vessel should be instructed to switch off their mobile phones. Portable or mobile phones should only be used in the accommodation after permission has been granted from the Master. This also applies to pagers, loudhailers etc. Whilst the vessel is alongside and engaged in cargo operations the ship’s radar equipment is not to be operated. 3.5.24 Fire Fighting Equipment All relevant fire fighting equipment should be ready and available for immediate use. 3.5.25 Connection and Disconnection of Hoses / Chicksans Connection and disconnection of hoses or chicksans will be supervised by an Officer ensuring that:


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flange faces are clean, smooth and dry; all bolt holes are fitted with a nut and bolt of the correct size; all nuts are fully threaded on the bolts; material, size and condition of gaskets to be used are suitable for intended discharge; all connections are tightened evenly; electrical continuity requirements are met;

3.6

STATIC ELECTRICITY

3.6.1

General Matter consists of equal numbers of positive and negative ions and under normal conditions is electrically neutral. This is true of oils, chemical products and other liquids. A redistribution of ions tends to occur when a liquid comes into contact with a solid, giving rise to the formation of an electric double layer where the ions adjacent to a liquid/solid interface are redistributed to produce a layer of ions of the same electrical sign. Close to this layer but slightly further away from the interface a layer of ions of the opposite sign will be formed. Elsewhere the distribution of ions remains unchanged. When the liquid and solid are separated, as in any pipe line flow, the ions in contact with the solid (pipe) tend to remain attached to the solid and the oil (or other liquid) loses some of its ions, thus becoming electrostatically charged. The separated charges will attempt to recombine, their success depending upon the electrical conductivity of the oil. Black oils, which contain high levels of impurities, have high electrical conductivity and charge recombination is rapid. Water also has high electrical conductivity. By comparison, most refined products (white oils) contain few impurities and charge recombination in such products is very slow. These products are known as STATIC ACCUMULATOR OILS . The rate of flow through pipes will influence the build-up of charge separation - the faster the flow, the faster the charge separation. Charge separation will also occur:

3.6.2

•

In the filling lines of tanks being loaded with white oils.

•

When oil mixes with water.

•

When air is allowed to "bubble" through white oils and splashing occurs at the surface.

•

When oil is splashed or sprayed.

•

When water droplets in a steam jet (or CO2 particles) leave a nozzle.

•

When water passes through tank cleaning machines at high pressure electrostatic charging of fine sprays or mists may result.

Cargo Operations During cargo operations a potential hazard exists: •

When the cargo being handled is static accumulator.


3.6.3


•

When the cargo being handled is at or above its Flash Point.

•

When the cargo is loaded into a tank containing flammable vapour.

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Electrical Continuity - Bonding and Earthing Static accumulator oils may be electrostatically charged by pipeline flow. When the charged liquid flows through non-conducting flexible ship/shore connections part of the cargo may be picked up by intermediate metal flanges and other metal parts, which are in contact with the liquid inside the hose. In order to prevent the accumulation of a dangerous voltage, all metal flanges and parts must be effectively bonded to maintain electrical continuity to earth through the shore or the ship's hull. Generally the bonding of the metal reinforcement in the hoses to their flanges will ensure this. When ship hoses are to be used for cargo transfer, the Chief Officer is to ensure that electrical bonding is checked prior to commencing operations. When there is an insulating flange at the shore manifold, intermediate flanges in the ship/shore hose will still be earthed by the continuous path to earth via the ship's manifold and hull. Investigations have proved that ship/shore bonding wires serve no useful purpose, and they are only to be connected on the insistence of the terminal. Under these circumstances the Chief Officer must ensure that the switch in the bonding circuit is open, before permitting connection to the ship. In addition the bonding wire is not to be connected to the manifold. Connection to the ship and subsequent disconnection may not take place unless:

3.6.4

•

All ullage ports are securely closed and no sampling, sounding or dipping of tanks is in progress.

•

No cargo, ballasting, tank cleaning or gas freeing operations are in progress.

Cargo Flow Velocity Charging of static accumulator oils by pipeline flow will be increased if water is present in the cargo. Charging to an even greater degree can be caused by the subsequent movement of water settling through the cargo in the tank. When the cargo first enters a tank any water on the bottom will be agitated and dispersed into the cargo to re-settle later and cause charging. This can continue long after loading into the tanks has stopped. To minimise the hazard, flow rates for static accumulator cargoes must be restricted during the initial stages of loading as follows: •

Into Tanks that are not Inerted

The flow velocity through the loading line into each tank is not to exceed 1 metre per second until the cargo has covered the filling inlet and the tank bottom longitudinals, or depth of 0.5 metres above the tank bottom has been reached, whichever is the greater. Thereafter the loading rate may be increased. Loading into tanks, which have not been inerted, is not permitted unless the agreement of the Company has first been obtained


•


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Into Tanks that are Inerted

Flow rates need not be restricted, however, at the start of discharge a slow pumping rate may be required by the receivers. 3.6.5

Ullaging and Sampling If the restrictions previously mentioned on flow rates are applicable, metal sampling cans and steel ullage tapes must not be used during loading or for thirty minutes after completion of loading the tank. These restrictions do not apply to the ship's permanent gauging system. In the event of failure of the ship's permanent gauging system M.M.C. gauges are to be used. The normal practice in Company vessels will be to operate the "closed loading " method by the use of automatic ullaging systems where fitted. On vessels not fitted with automatic ullaging systems, or where the ullaging system is non-operational, the normal practice will be to use M.M.C. gauges.

3.6.6

Loading Overall (Splash filling) (free Fall Loading) If the cargo has been electrically charged by flow through a shore pipeline, loading overall or splash filling will deliver it to the liquid surface in the tank where the hazard from electrostatic charging, in the presence of flammable vapours, is most likely to occur. For these reasons, therefore loading or transferring of flammable cargoes– by “loading overall” is not permitted - on the Company’s ships.

3.6.7

Pipeline and Hose Clearing Compressed air must not be used for clearing pipelines or ship/shore hoses back into a ship's tank if the cargo is a static accumulator and the tank contains flammable vapour.

3.6.8

Steaming Operations Water droplets issuing at high velocity in a steam jet may become charged by contact with jet nozzles and produce a charged mist. Steam must NEVER be introduced into a tank, which contains flammable vapour. If, as a result of hot washing, a tank contains a mixture of steam and flammable vapour, a tank washing machine or other conductor (whether earthed or unearthed) must NEVER be lowered into it. Such conductors may accumulate charge from the steam cloud.

3.6.9

Tank Washing with Water The injection of water under high pressure through tank washing machines gives rise to the formation of an electrostatically charged mist in the tanks or holds being cleaned. The degree of electrostatic charging varies in direct proportion to the pressure and to the total throughput of water.



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It has been found that higher electrical potentials are developed by single nozzle machines whereas twin nozzle machines, which rotate at a higher speed, develop opposite potentials at each nozzle thus producing rapidly changing potentials within the space which do not reach the high levels generated by single nozzle machines. Impingement of water jets on the tank structure causes disintegration of the jet, which gives rise to the formation of charge water droplets. The coarser drops all assume the same electrical sign while the finer mist takes the opposite sign. Excess water dripping from protrusions will form elongated droplets with pointed ends at, which may occur, a small "corona" type discharge, which could create a hazard under certain circumstances. A higher risk exists from a slug of water which, after descending through a charged mist, it becomes electrically charged, and on approaching an earthed probe may create an incendive spark between the slug and the probe. 3.6.10 Portable Pumps The use of portable pumps (such as Wilden or Graco types) can also create a risk of build up of static electricity. Such pumps, when used in hazardous environment, must therefore be properly grounded. This is normally done by means of a “grounding clamp”. This consists of a wire fitted with a ringeye, which is attached to one of the bolts on the pump. The other end of the wire has a clamp arrangement, which is to be secured to the nearest/best grounding point. After the ring eye has been mounted properly on the pump the connection must be tested with an Ohm meter to verify that there is a full electrical connection between the clamp and pump. (i.e zero resitanace.) All vessels must ensure that a suitable arrangement such as the above exists before using portable pumps in a hazardous area. 3.6.11 Tanker Explosions In the course of investigations into electrostatics, certain new factors have emerged which are relevant to the safety of tank cleaning operations, not only in very large tankers but in tankers of all tonnage’s. It has been demonstrated that electrostatic charging to the water mist, present in the tanks, exists under any cleaning condition, and that when washing operations are stopped the level of charge decreases only slowly in the tank, and can remain present for a long time, especially in the absence of ventilation. The following factors therefore need to be considered:•

In studying "charge concentration mechanisms", it has been found that insulated objects are not normally present in ship's tanks, but the use of sounding rods might present such a hazard.

•

When a sounding rod is lowered into a tank filled with charged mist, a high static charge can be fed into the operator via the wet suspension rope if the operator is insulated by the deck paint or his footwear. Such a charge accumulation has been shown to be sufficient to cause incendive sparking when the operator, the sounding rod, or rope, comes into contact with the ship's structure. This, of course, does not apply if the rod is lowered into a sounding pipe extending to the bottom of the tank.


•


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Portable tank cleaning machines are normally bonded to the ship's structure and furthermore, when in operation the washing water provides a path for the electrostatic charge to dissipate. However, these machines may sometimes become insulated objects and a potentially hazardous situation may exist in at least the two following cases;Where the bonding wire is defective. Where the hose is disconnected from the hydrant before lifting the machine out of the tank. Such disconnection, prior to lifting, is commonly done in order to drain water from the hose. A coat of paint in good condition is sufficient to insulate the hose flange from the steel of the deck. Under these conditions, when the machine is lifted an incendive spark may jump to the lip of the tank cleaning hole, either from the machine or from the securing rope or from the operator who guides the machine through the hole.

•

The following precautions are required to prevent the foregoing hazards: Not to use sounding rods through any deck opening other than the sounding pipe, either during tank cleaning, or for one hour after cessation of washing if the tank is being blown, or five hours if the tank is not being blown. To carry out checks on the electrical continuity of bonding wires on the tank cleaning hoses before each use. To keep the hoses connected to the hydrants until the machines are out of the tank. The draining of the hose can be done by loosening the coupling of the hose carefully to let the air in and by tightening the coupling again. It is emphasised that while the likelihood of all the factors necessary to lead to an incendive spark being present at any one time is remote, the fact that neglect of the foregoing precautions might lead to an explosion remains a possibility.

3.7

REMOVABLE BENDS, SPOOL PIECES AND FLEXIBLE HOSES Portable bends must only be connected when required for a particular operation. On completion of that operation they must be removed and the blanks properly fitted. In order to make them conspicuous, all portable bends, and spool pieces are to be conspicuously marked and labelled with intended purpose. Gaskets of the correct size and material are to be available, and must be used when connecting the bends, spool pieces or flexible hoses. Flexible hoses are to be pressure tested annually, marked with date/pressure and provided with test certificates. The electrical continuity of flexible hoses is to be checked before each use should there be any doubt about condition deterioration since the last routine testing. (Otherwise every three months). When removable bends, spool pieces or flexible hoses are being used, particular care must be taken to ensure that they are all in respects suitable for the intended cargo. Chemical tankers are referred to ship’s specific “P & A Manual” and IBC/BCH Code for full details.


3.8


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FLAME ARRESTORS All flame arrestors and screens, if fitted, must be maintained, in good condition and replaced if they deteriorate to the point where they will become ineffective. Passage of gas may be dangerously restricted if these devices become blocked. Flame screens must never be painted.

3.9

ELECTRICAL EQUIPMENT/FITTINGS. All electrical equipment and fittings outside the accommodation and machinery spaces must be intrinsically safe. Damaged electrical fittings must be isolated and not used until they are repaired. Particular care must be taken to ensure that portable electrical equipment such as radio telephones, pagers and electrical equipment cameras etc. are not used in hazardous areas. The batteries for portable equipment must not be changed on the open decks, and strict control to be put in place to ensure that the following are intrinsically safe: Hermetic Ullaging Equipment VHF/UHF radios Torches Gas detection Equipment Cameras when used in any dangerous areas, must not contain batteries or other electrical circuits, unless intrinsically safe Damaged portable equipment must not be used until it is repaired.

3.10 HYDROCARBON AND TOXIC GAS MONITORING When spaces are automatically monitored for hydrocarbons or appropriate toxic gases then no manual monitoring is required provided that the automatic equipment is operational and properly calibrated. Portable gas detection equipment is to be properly calibrated and ready to use at all times. Spaces adjacent to cargo compartments are to be manually monitored for hydrocarbon gas or other relevant toxins as appropriate to the cargoes carried within 12 hours after loading and thereafter daily and records maintained in the Deck Log Book. Pumprooms where fitted are to be manually monitored at least weekly on voyage for hydrocarbon gas and in addition any applicable toxic vapour and records maintained in the Deck Log Book During Cargo operations the pumprooms are to be monitored at least every two hours for hydrocarbon and toxic vapours, with the readings recorded in the Cargo Time Book.

3.11 SOUNDING ROUTINES A daily sounding routine is to be established on all vessels covering all ballast tanks, pumprooms, stools, chain lockers, void spaces and all empty cargo spaces and the sounding entered in the Deck Log Book.



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3.12 CARGO PUMPROOMS 3.12.1 Ventilation Correct use and set up of pumproom(s) ventilation systems are essential to ensure that pumproom(s) remain free from explosive or toxic atmospheres. Invariably the system fans are set up to make suction from below the bottom floor plates, i.e. from the bilge area. This gives full and proper circulation of all air in the pumproom to maintain a safe atmosphere. Additionally middle level suctions are available above the bottom floor plates. These are for emergency use only. In the event that flooding or saturated vapour builds up in the bilge area, they can be opened to avoid liquid or saturated vapour being drawn up the fan trunk and deposited on open decks, with the consequent pollution hazard. A notice is to be posted to each control level for the mid level flaps: “TO BE KEPT CLOSED EXCEPT IN CASE OF FLOODED BILGE”. Throughout cargo handling operations the pumproom ventilation system must be in continuous operation. Pumproom fans must be checked prior to and during cargo operations to ensure the correct direction of flow and that fans are mechanically in good condition. Noisy fans must not be operated until they have been checked to ensure that they are not generating mechanical sparks or heat at defective bearings. Defective fans must be repaired at the earliest opportunity. 3.12.2 Routine Inspection The pumproom is to be inspected as soon as possible after starting a cargo/ballast pump or commencement of loading. Inpsections are to take place at hourly intervals to ensure that there are no leakages. The inspection of the cargo pumproom is to include checks of the following: bilges are clean, dry and free of cargo product cargo/ballast pump bearing and casing temperatures Cargo/ballast pump and pipeline integrity Operation of ventilation system Monitoring of atmosphere. 3.12.3 Entry Procedures The Pumproom must be marked in the following manner:REPORT AT THIS POINT NO ENTRY WITHOUT Permission from the Chief Officer/OOW A valid Work Permit – Pumproom Space Entry Permit TNK 14 The ventilation having been in operation for at least 15 minutes The atmosphere having been tested for: Oxygen deficiency Flammable gas



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Toxic gas No one may enter the Pumproom unless the above conditions have been met. Entry procedures to pumprooms are divided into three categories a)

Normal Pumproom entry during cargo operations and tank cleaning must be made under an “Entry Permit”, using the Pumproom Space Entry permit TNK 14 system. Before commencement or operations the Chief Officer: OOW must complete page 1 of Form TNK 14

Where the cargo is known to contain dangerous toxicants portable detection for these toxicants must be made. Guidance shall be taken from the MSDS for the cargo in question. b)

When work is contemplated then: -Entry under these circumstances differs from section a) in that the work being carried out may result in the release of toxic vapours. Entry may also be necessary to make good some defect which has resulted in leakage of product and therefore hydrocarbon or toxic vapour.

Before entry the Officer or rating must in addition to all the requirements in section a) ensure that:Cold Work Permit SAF 05 is completed Entry may be necessitated when the space is not gas-free due to defective or inadequate ventilation, mechanical failure of valves, pipelines or pumps, or for any other reason when tests indicate the presence of flammable and/or toxic vapours. c)

Under these circumstances the entry is to be treated as an emergency operation and the Chief Officer is to personally supervise the entry. An Enclosed Spaces Entry Permit SAF 11 must be completed and the following procedures are to apply:-

Cold Work Permit SAF 05 is completed. No entry is to be permitted until the Enclosed Spaces Entry Permit has been completed and approved by the Master. In the absence of the Master his deputy is responsible for approving the Enclosed Spaces Entry Permit SAF 11. Note 1 Fixed Smothering equipment fitted in the pumproom in not to be operated if the gas level is in excess of 40%LEL. Note 2 Gas generation caused by product in the bilges can be reduced and minimised by spreading a layer of foam over the pumproom bilges.

3.13 VOID SPACES/DUCT KEELS AND PIPE TUNNELS Because of restricted natural ventilation these spaces may be oxygen deficient. In addition, they are adjacent to cargo holds and ballast tanks, so both hydrocarbon vapour and inert gas may leak into



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them. It must be recognised that the rescue of an unconscious or injured person may be very difficult. Where the Classification Society rules do not require the permanent lighting systems in these spaces to be isolated during oil trading, the following procedures are to be complied with in order to eliminate the hazards that could result from damaged flame proof fittings.

The space must be tested and proven gas free, before the lights are switched on. The mechanical ventilation system is to be in operation before the lights are switched on, and must remain in operation until after the lights are switched off.

3.14 LEAKAGE INTO VOID AND BALLAST SPACES Leakage of cargo from the cargo tanks into the permanent ballast tanks or void spaces can create a potentially serious pollution problem. Structural failure at known weak points therefore requires monitoring. In order to monitor the integrity of double hull spaces a procedure for checking these spaces for the presence of hydrocarbon and or relevant toxic gases is to be established. As a back-up, a system of sounding round all spaces is to be employed. This system may be established as part of the daily sounding routine. During the ballast voyage the cargo spaces are to be checked for the ingress of water from the ballast tanks. Depending on the cargo carried it is essential not only to test the ballast tank for oil content but also the atmosphere for toxic gases and/or oxygen deficiency before entering the tank to carry out repairs. It must be remembered that the requirements of the Work Permit Entry into enclosed spaces must be complied with.

3.15 WORKS IN CARGO AND BALLAST TANKS When it is necessary for crew to work in cargo or ballast tanks the Company requirements for Enclosed Spaces Entry must be complied with in all respects. The initial entry must be made by a responsible Officer to carry out further testing before allowing the crew to enter the tank. During the time the crew are working in the tank a responsible Officer must be in attendance. When any cleaning, repairs or maintenance work has been carried out in a cargo or ballast tank, the space must be carefully inspected by a responsible Officer after all work is completed to ensure that all tools, equipment, materials and debris have been removed and that no damage has been caused to coatings and/or fittings.

3.16 ACCIDENTAL SPILLAGES Ships personnel must maintain a close watch throughout cargo operations to ensure that any escape of cargo does not go unnoticed. In this respect, it is essential that all valves are closed if not in use.



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Personnel operating inert gas plants must be aware that, with some inert gas generators, there is a risk of oil pollution via the cooling water discharge when the burner does not ignite in its start cycle. Where such a risk exists it is better to start the generator before the vessel arrives at the berth. Cargo or bunker tanks which have been “topped-off” must be checked frequently during the remaining loading operations to avoid an overflow. If an accidental spillage or leakage of cargo occurs during any operation, the relevant operation must be stopped immediately until the cause has been established and the defect corrected. All Company vessels are supplied with an approved outfit of clean-up materials as specified under the U.S. Oil Pollution Act of 1990 and MARPOL Annex I. Clean up materials must be available at the bunker or cargo manifold, for the prompt removal of any spillage on deck. Portable salvage pumps must be deployed at the after end of each side of the main deck. Chemicals used for clean up on deck must not be allowed to enter the water unless permission has been obtained from the harbour authorities. Should an cargo spill accident take place then the appropriate authorities, as detailed in the vessel’s Oil Spill Response Plan (US waters), or SOPEP (other waters) must immediately be informed. The contact sheet required by the Plan must be completed prior to arrival in port.

3.17 SEA VALVES AND OVERBOARD DISCHARGE VALVES Particular care must be taken to ensure that no leakage of cargo takes place through overboard discharge or sea suction valves when starting or running cargo pumps. Manual valves are to be chained/locked. These valves are to be air pressure tested regularly for integrity and a log entry made. Officers should refer to the ICS/OCIMF Publication “ Prevention of Spillages through Cargo Pumproom Sea Valves”.

3.18 DECK SCUPPERS Prior to any cargo operation taking place all deck scuppers are to be plugged. Careful attention is to be given to keeping scuppers dry and clean. Mechanical type scupper closures are required to be used in USA ports.

3.19 MANIFOLD SAVEALLS Manifold savealls are to be provided under each manifold connection. These are to be kept clean and dry wherever possible, with any cargo spillages being drained at the earliest opportunity. Operational contamination is to be prevented by use of collection drums during connection/disconnection.



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3.20 SHIP TO SHIP TRANSFER 3.20.1 General This section outlines the preparations and procedures for ship to ship transfer (STS) operations with special emphasis on the safety aspects of cargo transfer. It deals with transfer operations between ships and/or barges when moored alongside. 3.20.2 STS at the roads / at sea In case of Ship to Ship transfer at the roads, or at sea, the guidelines as mentioned in the OCIMF “ SHIP TO SHIP TRANSFER GUIDE” must be followed. 3.20.3 Responsibility Each Master remains fully responsible for the safety of his own ship, its crew and cargo, and must not permit safety to be prejudiced by the actions of the other Master concerned. 3.20.4 Communications Satisfactory communications between the two ships involved are an essential requirement for a successful ship to ship transfer operation. Communications between the two ships should preferably be in the English language unless both vessels have a common language. On each ship the officer on watch, who is in charge of cargo transfers, should at all times have reliable means of communications. Intrinsically safe hand-held radios are the preferred method. 3.20.5 Operational considerations Pre-planning of the operation should ensure that the ships have compatible critical features of design and equipment and thus safe and efficient communications, berthing/unberthing, hose handling and cargo transfer operations can be maintained. 3.20.6 Notification of authorities It may be necessary to obtain permission of a port authority for a STS cargo transfer. The Master and the ships’ operators/agents are responsible for obtaining such permission and giving all necessary information and notification as requested by the port authorities. The local ships’ agent(s) should inform the ships involved in a STS transfer of all requirements and regulations imposed by the port authorities for a STS cargo transfer within their area of jurisdiction.



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3.20.7 Cargo transfer operations Before commencing cargo transfer the receiving ship should obtain all relevant information about the cargo to be transferred, such as but not limited to the following: •

full chemical name of each product, UN- number and pollution category, if applicable;

•

safety data sheet of each product;

•

any special handling instructions.

If the product is inhibited against dangerous self-reaction the certificate of inhibition should be obtained from the other ship, together with details of any further inhibitor which may need to be added. Transfer hoses to be used must be of sufficient length to avoid stressing and chafing throughout the transfer. Hoses must also be suitable for the product to be transferred and certified and tested as appropriate. Before transfer commences satisfactory communications should be established between essential personnel on both ships incompliance with the STS checklist. The receiving ship should advise the unloading ship of the maximum flow rate it can accommodate for each product. Transfer should begin at a slow rate until both ships are satisfied that the transfer system is safe for transfer. Closed transfer should be practised where flammable and/or toxic cargoes are involved. Vapour hose connection is required when handling toxic cargoes to return vapours to the unloading ship. Listing and extremes of trim should be avoided. Throughout the transfer a responsible person equipped with a hand-held portable transceiver must be stationed at or near the pump controls. In addition a responsible person must be stationed at or near the manifold to monitor the transfer hoses. Any spill or pollution should be reported as per the SOPEP/VRP as appropriate. In the event of any of the following, transfer should be suspended: •

problems with hoses or moorings;

•

marked deterioration in the weather;

•

excessive movement by one or both ships which may cause direct contact between the ships;

•

electrical storm in the near vicinity when handling low flash point cargo(es).

3.20.8 Emergency It is impossible to anticipate every emergency which could arise, and therefore impossible to indicate precise remedial action. The Master of the lightening/receiving vessel should make available a copy



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of the STS lightening Contingency Plan to the ship To Be Lightered (STBL) in accordance with Chapter 10 of the ICS/OCIMF Ship to Ship Transfer Guide. The Plan should be agreed between both ships before STS transfer operations commence. The Masters involved should assess the situation and act accordingly, bearing in mind that incorrect decisions can compound the emergency and increase the peril for one or both ships. The following actions should be taken or considered in the event of any emergency arising during STS operations: •

Alert crews.

•

Stop all cargo transfer.

•

Take up emergency stations in standby condition.

•

Send mooring gangs to stations.

•

Clear and disconnect hoses.

•

Ready engines for immediate use.

•

Alert port authorities.

THESE ARE EXAMPLES OF MAJOR ITEMS FOR CONSIDERATION. IN ADDITION, MASTERS SHOULD DECIDE, PARTICULARLY IN THE CASE OF FIRE, WHETHER THE SHIPS SHOULD REMAIN ALONGSIDE EACH OTHER.

CHEMICAL TANKER MANUAL SECTION 4 – CARGO PLANNING , HANDLING AND STOWAGE


4.

CARGO PLANNING, HANDLING AND STOWAGE

4.1


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VMS/CHM/01 01 1 of 10

The following reference publications are to be read in conjunction with this section: Publication

Location

SOLAS - 74 as amended Master MARPOL – 73/78 as amended Master International Safety Guide for Oil Tankers and Manuals (ISGOTT) Chief Officer Ship’s “Procedure and Arrangements Manual” (Approved by Class) Master Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk Master Ship’s “VEC System Operating Manual” (Approved by Class) Master BCH/IBC Code Master CFR 33 Parts 124 to 199 Master Guide to Port Entry Master Tanker Safety Guide (Chemicals) Chief Officer Ship to Ship Transfer Guide (Petroleum) Chief Officer Safety in Oil Tankers Chief Officer Safety in Chemical Tankers Chief Officer IMDG Code Chief Officer Supplement to IMDG Code (Including MFAG and Ems) Chief Officer SOPEP Chief Officer Clean Seas Guide for Oil Tankers Chief Officer FOSFA (for Oils, Seeds and Fats) Chief Officer Prevention of Oil Spillage through Cargo Pumproom Sea Valves Chief Officer CHRIS Guide (USCG) Chief Officer MSDS for particular cargo carried Chief Officer

4.2

COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Company Form No MAR 08 TNK 01 TNK 04

4.3

Title Cargo and Loading Discharge Plan Pre arrival and Commencement – Cargo Operations Checklist Prior to Use of Vapour Emission Control System Checklist

GENERAL This procedure describes the procedure to be followed concerning the pre-planning and stowage of cargo on receipt of instructions from Charterers The precautions outlined should be considered as general guidance only, as there are considerable variation in the design of cargo containment and cargo handling systems. Specific instructions in the



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VMS/CHM/01 01 2 of 10

form of Critical Operations Checklists (see VMS/SEM/01 3.6) should be prepared for individual vessels. The cargo containment and handling systems have been designed and constructed in accordance with the requirements of the IBC/BCH codes, the SOLAS convention and the MARPOL 73/78 convention to safely transport and handle the chemicals the ship is certified to carry. However, the required levels of safety in cargo-operations can only be achieved if all parts of systems and equipment are maintained in good working order. Similarly, the personnel involved in cargo operations must be fully aware of these instructions, their duties and be thoroughly trained in the correct procedures and handling of the equipment. Before and during all operations involving the cargo, ballast and bunkering systems, the Master must ensure that the precautions required by the VMS and relevant checklists are fully observed. Reference is to be made to the publications listed in this section as well as equipment operating and instruction manuals. Each vessel, which is certified for the carriage of noxious liquid substances (NLS) in bulk, is provided with a Procedure and Arrangements Manual (P & A Manual). The purpose of this Manual is to identify the arrangements and equipment to enable compliance with Annex II of MARPOL 73/78 and to identify for the ship’s officers all operational procedures with respect to cargo handling, tank cleaning, slops handling, residue discharging, ballasting and deballasting, which must be strictly followed.

4.4

RESPONSIBILITY It is the responsibility of the Master to ensure that the officers and crew are properly and correctly informed of their duties and understand how to fulfil them. The Master, or an officer appointed by him, is responsible for the safety of the vessel and all cargo operations. The responsible officer should be present at all times and satisfied that all equipment under his care is in good working condition. In port, the Master should ensure that there is proper liaison between the responsible officer (Chief Officer) on the ship and his counterpart at the shore installation. The Chief Officer should establish the program for all cargo operations and the procedures to be adopted in the event of an emergency. Details of emergency contact names, positions, telephone numbers etc. should be distributed before cargo operations begin. Any special safety requirements of the shore installation should be brought to the attention of those concerned.

4.5

GENERAL CYCLE OF CARGO OPERATIONS Every chemical tanker should have a Procedure and Arrangements Manual that gives specific operating instructions. The following sequence outlines a general cycle of operations, and supplementary comments are made where relevant. •

Preparation for cargo loading - Inerting/purging - Loading - Transport - Preparation for discharge - Discharge - Ballasting - Tankcleaning/gas-freeing.



4.6

VOYAGE PLANNING & STOWAGE OF CARGO

4.6.1

Description

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VMS/CHM/01 01 3 of 10

The Master is by law and in practice ultimately responsible for the correct stowage of the cargo. He must take all parameters such as, but not limited to the following into consideration; stress, stability, trim, list, heating, segregation/compatibility, quantity, last cargoes, customer requirements and present status of tanks and their equipment. As the parameters are numerous the Master must receive all available cargo details including voyage orders, cargo information and Charterer’s requirements well in advance. Checklists are to be used as a reminder. 4.6.2

Delivery of voyage orders The voyage instructions will be issued by the management office and sent to the vessel by telex, fax, e-mail or other available means. The Master must confirm receipt and understanding to the management office accordingly.

4.6.3

Voyage Orders Contents

Typical voyage orders will contain the following elements: • • • • • • • • • • • • • • • • •

Voyage IMO ship’s type number Rotation (Loading –Discharge ports) Cargo quantity, commodity and options Charterer Load port and discharge port Specific gravity of the cargo at 20°C. Heating instructions Inerting, Padding and/or purging instructions US Coast Guard number and pollution category C/P date Laycan (Laydays and cancelling date) Special requirements by charterers Special characteristics of ports/berths Stowage proposal by Charterers Bunker proposals Any additional relevant information.

The following are to be considered when accepting cargo(es):

• • • •

Compatibility of cargo with vessel’s tanks, tank coatings, pumps and equipment; Reactivity and compatibility with adjacent cargoes (segregation requirements); Physical properties of the cargo; If according to the vessel’s “Certificate of Fitness” the cargo is permitted to be carried;



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VMS/CHM/01 01 4 of 10

• Previous cargo tank history and future cargoes; • Customers requirements; • Future trading commitments. • If heat source adjacent The Master should advise the management office of any disagreement, or inability to comply, with the instructions. 4.6.4

Cargo quantities The cargo quantities are planned by the Master and checked in relation to the voyage orders with regard to: • • • • •

4.6.5

Loading capacity (load calculation) International Load Line Zones in trading area Expected trim, heel, intact and damage stability Sheer force and bending moment stresses during the various stages of loading and discharging Draft and passage limitations en route and in ports of destination

Filling limits The following is to be used for the determination of the filling limits of the cargo tanks in which lowboiling point chemical products are allowed to be carried. (Cargoes with a vapour pressure greater than 1.013 bar absolute at 37.8 °C) The setting pressure of the safety valves is: 0,6 bar the maximum volume of cargo to be loaded in a tank is determined , in compliance with Para. 15.14.7.2 of IBC Code, as: VL = 0.98 V (ρR/ρL) Where

V = volume of the tank ρR = relative density of cargo at the reference temperature (R) ρL = relative density of cargo at the loading temperature

R = reference temperature, i.e. the temperature at which the vapour pressure of the cargo corresponds to the set pressure of the pressure –relief valve 4.6.6

Cargo Quantity Options Abbreviations are used in the instructions expressed as percentages and as follows: • • •

MOLOO MOO LOO

More or less Owners option More Owners option Less Owners option


• • • • 4.6.7

MOLCO LCO MCO MIN/MAX


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VMS/CHM/01 01 5 of 10

More or less Charterers option Less Charterers option More Charterers option Exact quantity

Cargo equipment defects It is the Master’s responsibility to inform the management office immediately regarding any cargo equipment defects which might influence the stowage to prevent cargo commitments being made to which cannot be adhered to as a consequence of these defects.

4.6.8

Stowage Limitations of Cargo Tank Structure and Fittings on Chemical Ships Attention should be paid to stowage limitations due to cargo tank structures and their fittings, i.e. the specifications of a cargo tank will limit product weights and quantities which can be loaded in that tank. Refer to ship specific Certificate of Fitness, also the BCH/IBC Codes, for lists of cargoes and tank types suitable for their carriage.

4.6.9

Oil and Hazardous Material Transfer Procedure Prior to each transferring of oil or hazardous cargo to or from the vessel and from tank to tank within the vessel the Chief Officer has to prepare and submit to the Master for approval an Oil or Hazardous Material Transfer Procedure as required by 33 CFR 155.720. The contents of Transfer Procedure should comply with the requirements detailed in 33 CFR 155.750. On Company managed vessels the requirements of this section are applicable to all hazardous material transfer operations irrespective of the ship’s trade area, and are not limited to US waters only.

4.6.10 Cargo Loading/Discharge Plan For quick reference throughout the cargo operations and in conjunction with the Transfer Procedure the Chief Officer is to prepare a loading/discharge programme on Form MAR 08, which is to include, but not be limited to, the following: •

Final ullages for all loaded tanks.

•

The order of cargo/ballast tanks to be filled/emptied together with the expected time schedule showing which pumps (if applicable) would be in use.

•

The number of controlled stages required depending on intended cargo operation and ship’s design.

• •

The required ballast condition for each stage of the operation. The expected stress, stability and draught conditions at each stage of the operation.

•

The operating envelope of shore loading/discharge arms The Cargo Loading/Discharge Plan is to be approved by the Master and signed by each Officer and Pumpman involved in the cargo operations. This plan is to be discussed and agreed in writing with the terminal personnel as described in these procedures.


4.7


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VMS/CHM/01 01 6 of 10

RETENTION OF SLOPS ON CHEMICAL TANKERS All processing and discharging of slops on tankers which are carrying a cargo of noxious liquid substances in bulk is to be in strict compliance with the requirements of Annex II of MARPOL 73/78 and procedures described in the approved ship’s specific Procedure and Arrangements Manual (P & A Manual). The above regulations (the latest amended version) must be available on board, and consulted before the loading of any noxious cargo is considered. All operations with respect to a chemical cargo which take place on board the vessel, including discharge into the sea or removal by ventilation of residues, is to be properly recorded in the Cargo Record Book for Ships Carrying NLS in Bulk. Substances posing a threat of harm to the environment are divided by MARPOL 73/78 Annex II into four Categories – A, B, C and D. Category A substances are those posing the greatest threat to the Marine Environment, whilst Category D substances are those posing the smallest threat. Water contaminated with chemical cargo (e.g. tank washings) may be discharged ashore, into barges and, under certain circumstances, into the sea. When washing tanks, which contained special cargoes, it is preferable to wash each tank separately and pump the washings independently to the shore, barge or sea rather than accumulate an unknown mixture in a slop tank. If tank washing or slops are to be transferred to a barge alongside the Ship to Ship Transfer Guide is to be followed, and it must be ensured that the necessary hose connections are properly made. Barge personnel must be acquainted with the nature of the hazards and with the safety precautions, which must be observed in the interest of both parties. Under no circumstances must water with noxious cargo be discharged overboard into port or enclosed waters, without the express permission of the appropriate authority. At sea, water contaminated with cargo must only be discharged overboard when absolutely necessary, and in strict compliance with Annex II of MARPOL 73/78 and ship’s P&A Manual. To minimise the risk of vapour or liquid cargo blowing back on board, water contaminated with cargo is, whenever possible, to be discharged overboard through a designated overboard discharge on the side opposite from the wind, taking into account the location of seawater intakes. Protective clothing must be worn by personnel on deck. Particular care must be taken not to intake the noxious vapour into ship’s accommodation and engine room. Alteration of the ship’s course and/or speed must also be considered to reduce the risk. When chemical tankers are carrying a cargo or part cargo of oil in bulk they must also comply with the applicable requirements listed elsewhere in this Manual.

4.8

PLANNING OF EQUIPMENT, BUNKERS, STORES ETC. It is the responsibility of the Master to plan equipment and supplies for the intended voyage such as, but not limited to the following: •

Bunkers and lubricating oils

•

Nautical publications

•

Safety equipment

•

Provisions and freshwater


4.9


: : :

•

Cargo care material

•

Tank cleaning chemicals

•

Cargo safety equipment- Draeger tubes fort he cargoes to be carried

•

Demiwater (distilled water) if required

•

Additional medicines (for cargo)

•

Nitrogen as required.

•

Cargo heating.

VMS/CHM/01 01 7 of 10

PROCEDURES, DOCUMENTS AND CONVENTIONS

The following conventions/rules, procedures and manuals must be complied with when preparing/planning cargo loading operations. •

Load Line Convention

•

IBC Code

•

Certificate of Fitness

•

Ship’s stability information

•

Resistance list for stainless steel

•

Resistance list for cargo tank coatings where applicable

•

Cargo hose resistance list

•

MEPC 2/Circ.

•

Product information

•

Chemical Hazard Data Sheets / Material Safety Data Sheets

•

Tank filling Limits

•

P&A Manual

•

U.S. Coastguard Compatibility Chart (See section 16)

4.10 VAPOUR EMISSION CONTROL (VEC) SYSTEMS Where required VEC is to be used and operated in accordance with current regulations and instructions contained in the vessel’s VEC System Operation Manual and in conjunction with the requirements and provisions of the shore installation. Masters and Officers must be aware that significant operational and safety implications are present, as the shore and the ship are effectively joined together as one unit. The primary hazards include: •

The ship loses effective control of the tank atmosphere pressure, and is directly influenced by any changes which may occur within the terminals system. It is therefore most important that associated pressure sensing devices on the vessel are well maintained. It is also essential that individual cargo tank P.V. valves are properly maintained and operate correctly.



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VMS/CHM/01 01 8 of 10

•

Vessels fitted with a VEC system must have an independent overfill alarm providing audible and visual warning. These are to be tested at the tank to ensure their proper operation prior to commencing loading, unless the system is provided with an electronic self-testing capability. Fixed gauging systems must be maintained in a fully operational condition at all times.

•

Tanks must not be opened to the atmosphere for gauging or sampling when connected to the shore vapour collecting system, unless the cargo being handled permits, loading to the tank is stopped, the tank is isolated from any other tank being loaded, and precautions are taken to safely reduce any pressure within the cargo tank vapour space.

•

The ship’s system is to be provided with means to collect and drain condensed vapour, which may have accumulated in the pipelines. Drains must be installed at low points within the ship’s piping system. These drains must be checked clear before each use of the VEC system and on a regular basis when the system is not in use.

•

Care must be taken to ensure that no possibility of misconnection of Vapour and Liquid hoses can occur. The ship’s vapour connection is to be clearly identified. The outboard 1.0 metre of piping is to be painted with yellow and red bands (0.1m red, 0.8m yellow, 0.1m red) and marked with the word “Vapour” (not less than 50mm high). The vessel’s presentation flange is to be fitted with a stud to prevent an incorrect connection.

•

To prevent electrostatic build up within the vapour return pipework, all pipework is electrically bonded to the hull. The integrity of these connections is to be periodically checked.

Ship’s personnel are to make themselves fully aware of the operation of the VEC system on board. Reference to the approved operations manual is to be made. The transfer procedure, required by section 4.6.9 of this manual must contain a description of the VEC system as listed in 33 CFR 155.750 (d). The full procedures for the use of the VEC system are to be clearly agreed at the pre-transfer meeting between the Terminal Representative and the Chief Officer. All tests and inspections required by 33 CFR 156.170(g) must be carried out prior to transfer operations. Checklist 04 is to assist the responsible officer with VEC operations. This checklist is to be completed prior to commencement of any VEC operation. NOTE: The VEC system must be inspected and approved/certified by the USCG prior to use in the USA. The TVEL/LOC will reflect this approval, being endorsed accordingly.

4.11 SHIP-TO-SHIP (STS) TRANSFER USING VEC SYSTEMS Before carrying out such an operation reference is to be made to the operational guidelines contained within ISGOTT and other applicable reference publications. The technique is properly described as Vapour Balancing. Ships carrying out this operation are to be inerted if flammable cargoes are involved. Before commencing transfer the following operational precautions must be complied with as a minimum.



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VMS/CHM/01 01 9 of 10

•

At least one of the vessels must be able to permanently monitor the oxygen content of the vapour stream. The sample point must be close to the manifold and audible and visual alarms are to be available should the oxygen content exceed the agreed value.

•

The oxygen content of all tanks in the common system is to be maintained at a level no higher than the agreed value.

•

The vapour transfer hose is to be purged of air using inert gas or nitrogen until the oxygen content is below the agreed value before transfer commences.

•

Vapour manifold valves are not to be opened until the receiving vessel system pressure exceeds that of the discharging vessel system pressure.

During the Cargo Transfer: •

Operations are to be terminated if the oxygen content of the vapour stream exceeds the agreed value. Operations are not to be resumed until the oxygen content in the receiving ship has been reduced below the agreed value.

•

There is to be frequent monitoring of both ship’s IG pressures with cross comparison on a regular basis and at least hourly. Transfer volumes are to be compared on the same basis. No air is permitted to enter the tanks of the discharging ship at any time

4.12 PRE-TRANSFER SURVEY AND LOG ENTRIES Prior to any oil or hazardous material transfer operation a survey of the vessel and her cargo systems is to be carried out. The survey must include the examination and testing of all items listed in Chapters 6, 7 & 10 of the International Safety Guide for Oil Tankers and Terminals, and as applicable to the vessel. These Chapters are: •

Chapter 6 operations.

Precautions before and during cargo handling and other cargo tank

•

Chapter 7

Handling of cargo and ballast.

•

Chapter 10

Fixed inert gas system.

Special attention must be paid to the following: • • • • •

That strainer covers, inspection plates, and drain plugs are in position and secure. All drain valves in the pumproom and on deck are closed. All bulkhead and pump glands are in good order, greased and adjusted as necessary. All pump glands, drain cocks and bearings are checked at least hourly for overheating when the pumps are operating. Pump trips are to be tested prior to the commencement of each cargo operation and the result logged.



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VMS/CHM/01 01 10 of 10

The majority of the items listed in ISGOTT 6, 7 and 10 are included in the standard ship/shore checklist, however not all, and it is essential that Masters review the requirements of this chapter prior to arrival. Wherever possible equipment tests are to be carried out prior to arrival. The majority of checks can not be completed until immediately prior to the cargo transfer operation, and the Master must ensure that these are carried out. On successful completion of all tests and checks and prior to commencing cargo operations, a log entry is to be made. The requirements of this section are applicable to the USCG requirements, therefore, in USA waters and ports this log entry must state the following: “Cargo System Survey as required by 33 CFR 157.435 (1) completed and all items as applicable to this vessel found in order”. The above surveys are to be carried out under the supervision of the Chief Officer and Chief Engineer. Immediately prior to commencing cargo operations the Chief Officer must personally assure himself of the correct setting of the valves in the cargo system, including the P/V valve and associated venting system. In the event of any problems the Company is to be advised immediately.

CHEMICAL TANKER MANUAL SECTION 5 – SAFE STABILITY

5.

SAFE STABILITY

5.1



: : :


The following reference publications are to be read in conjunction with this section:

5.2

Publication

Location

Ship’s “Trim and Stability Data/Manual” (Approved by Class)

Master

Ship’s “Procedures and Arrangements Manual”(Approved by Class)

Master

CHECKLISTS There are no Checklists applicable to this section.

5.3

COMPANY FORMS There are no Company Forms applicable to this section.

5.4

GENERAL The Chief Officer is responsible to the Master for the safe loading or ballasting of the vessel so that stability, stress and trim are acceptable throughout the voyage and that the vessel remains manageable in a seaway without excessive shear forces, bending moments, pounding, or vibration. The Chief Officer must ensure that the loading or discharging sequence is such that the vessel’s stability is never compromised and that permitted stress limits are never exceeded. Full and effective use must be made of the ship’s loading computer for both cargo and ballast operations and voyages. During cargo and ballast operation stability and stresses are to be checked hourly and printed records maintained on board. At sea the ship must never be loaded to a deeper draft than that permitted by the Load Line Regulations.

5.5

STRESS MONITORING SYSTEM Some vessels may be fitted with strain/stress gauges, which will automatically alarm at pre-set levels. Whilst this equipment provides valuable information it is essential that an accurate cargo/ballast plan is calculated and that stresses will remain within acceptable limits. The vessel must not be loaded/discharged purely on the strain/stress gauges. If during cargo/ballast operations the stress alarm sounds, all operations must stop until the situation is appraised.


5.6

STABILITY OF BULKHEADS)


DOUBLE

HULL

VESSELS

(WITHOUT

: : :


CENTRE

LINE

Officers must understand the stability aspects of double hull vessels. In contrast to conventional tankers which are inherently stable, it is recognised that double hull structures which do not have a centre line bulkhead have potential problems in that large free surface effects may be encountered at various stages of cargo and ballast operations. As a consequence, a loss of GM may result in serious stability problems. It must be stressed that Masters and Officers must be fully aware of this potential problem, and that all cargo and ballast operations are conducted strictly in accordance with the vessel’s approved loading manual. Changes to cargo plans must be fully assessed before the revised plan is undertaken. All ships are supplied with stability data, and loading and unloading instructions to comply with statutory requirements. These instructions are to be carefully studied and followed. Generally, these instructions will specify a maximum number of tanks, which may be slack at any one time. Sometimes it may be necessary to adjust the quantity of cargo to be loaded in order to avoid slack tanks. Where double bottom ballast tanks extend across the whole width of the vessel, the free surface effect of water in these tanks will be as great as that of full width cargo tanks and account must be taken of this fact. The Cargo Loading/Discharging Plan described in Section 4 must also take into account the problems of free surface and any limitations on the number of tanks which may be slack at any one time. In order to ensure adequate monitoring of the vessel’s stress and stability condition, calculations must be made and recorded, using the vessel loading computer, on an hourly basis during cargo and ballast operations. If a loss of stability becomes evident during loading or discharging, all cargo, ballast and bunker operations must be stopped and a plan prepared to restore positive stability. If the vessel is at a terminal this plan must be agreed with the terminal representative and the cargo hoses are to be disconnected. In all cases the Master shall positively verify the number of allowed slack tanks and post a clear notice of instruction according in the cargo control room. Where the stability manual does not state the maximum number of slack tanks allowed then the following rule shall be applied and the GM verified by the loading computer to be sufficient to maintain positive stability at all times. No. of Centre Tanks

Maximum No. Slack

9 6

5 3

Simultaneously a maximum of 2 pairs of ballast double bottom tanks are allowed to be slack.


5.7


: : :


SLACK TANKS AND SLOSHING It is essential that Masters and Officers be aware that the partial loading of a cargo tank with cargo ballast may present a potential problem. The combination of free surface and the flat bottom can result in the generation of wave energy of sufficient power to severely damage internal structures and pipelines. The movement of liquid within a cargo tank when the vessel is rolling or pitching in a seaway is also called “sloshing”. In general the negative effects of sloshing can be summarised as follows: •

The slamming effect of the liquid inside the tank may result in serious damages to the tank structure and fittings.

•

Even a slight rolling and pitching motion can generate the main source of ignition – an electrostatic charge. An electrically charged mist can also occur in the tank partially filled with a mixture of oil and water, such as dirty ballast, tank washings or slops.

•

The effect of free surface reduces the ship’s GM and may even lead to a loss of stability.

In order to eliminate these problems, slack tanks must be avoided wherever possible, and it is imperative that no cargo tank, unless so designed and permitted by Classification, is allowed to remain in a slack condition whilst the vessel is at sea. The Ship’s Trim and Stability manual approved by Classification and/or the Appendix to the Classification Certificate must be referred to on this matter.

CHEMICAL TANKER MANUAL SECTION 6 – PREPARATION FOR LOADING AND LOADING OPERATIONS


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VMS/CHM/01 01 1 of 16

6.

PREPARATION FOR LOADING AND LOADING OPERATIONS

6.1

REFERENCE PUBLICATIONS The following reference publications are to be read in conjunctions with this section:

6.2

Publication

Location

International Safety Guide for Oil Tankers and Terminals (ISGOTT)

Chief Officer

Ship’s “Procedure and Arrangements Manual” (Approved by Class)

Master

Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk

Master

Ship’s “VEC System Operational Manual” (Approved by Class)

Master

Ship to Ship Transfer Guide (Petroleum)

Chief Officer

Dr Vervey Tank Cleaning Manual

Chief Officer

COMPANY FORMS The following Company Forms are to be used in conjunction with this section:

6.3

Company Form No

Title

MAR 02 MAR 03 MAR 05 MAR 06 MAR 08 TNK 01 TNK 02 TNK 03 TNK 06 TNK 12 TNK 13 TNK 15

Port Log Notice of Readiness Deadfreight Statement Protest of Difference Between Ship and Shore Figures Cargo Loading and Discharge Plan Pre Arrival and Commencement of Cargo Operations During Loading Operations Checklist Completion of Cargo and Pre Departure Checklist Ullage Report Dry Receipt Certificate of Slops Vessel Experience Factor (Load)

PREPARATION FOR LOADING OPERATIONS This section describes the preparation of tanks, lines and associated equipment to meet the particular requirements of the expected cargoes. (See section 7 for details of special loading considerations for specific cargoes). Prior to loading the relevant tanks and associated loading equipment must be checked for technical readiness and their acceptability for the next cargo.


6.4

TECHNICAL READINESS

6.4.1

Visual


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VMS/CHM/01 01 2 of 16

Visual inspection of the tank, tank openings, and equipment has to be carried out. Special attention has to be paid to: • • • • 6.4.2

Tank dome / hatch Butterworth opening Ullage opening Packing

Tests / Checks The following tests / checks have to be carried out: • • • • • •

6.4.3

High – Level alarms Level gauging system P/V valves Heating coils for tightness (heating coils may need to be blown clear of water if not required for heating cargo) Cargo lines pressure testing if required by charterer before loading. Tank tightness

Preparation Prepare the following, if applicable: • • • • • • •

6.4.4

Manifold- reducer-ASA/Din Vapour return line Prepare / check jumper hoses or fixed connections. Nitrogen system Closed loading Decontamination shower and eye-wash Off shore manifolds to be blanked off, except where jumpers may be in use.

Safety Post stowage plan, cargo operation forms and chemical hazard data sheet/MSDS. Brief crew on the following: • • • • •

6.4.5

Risk level of the cargo(es) to be loaded Chemical protective clothing to be worn, when dealing with the cargo Fire fighting equipment to be used What to be done in case of spillage Additional medical equipment

Cleanliness Check the tank for cleanliness by carrying out the appropriate tests for chlorides, hydrocarbons, nonsolvent materials etc. in view of the charterer’s requirements for the cargo to be loaded.



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VMS/CHM/01 01 3 of 16

Reference is made to the ‘Tank Cleaning Manual’.

6.5

TANK ACCEPTANCE & PREPARATION

6.5.1

General This procedure describes the tank preparations required and procedures relating to tank acceptance immediately prior to commencement of loading. The type and scope of the testing varies with the cargo requirements.

6.5.2

Visual inspection Visual inspection can be done either from the deck through the tank opening or by entering the tanks. If the tank is to be entered particular attention has to be paid to the risks of lack of oxygen, toxic and/or explosive tank atmosphere. Always consider the tank ‘dangerous’ and act according to the Enclosed Space Entry procedures. The cargo line system can be checked for residual cargo at the manifold and by opening draincocks and plugs in the cargo line.

6.5.3

Odour check Some cargoes require to be loaded in odour free conditions. It is important that tanks are cleaned accordingly and presented free of odour.

6.5.4

Wall wash tests Depending on the product to be loaded and the previous product, contamination tests will be carried out with indicators. There are usually tests as follows: •

Chlorides

•

Hydrocarbons

•

Inhibitor residues

•

Lead compounds

•

Permanganate time test (PTT)

•

pH–tests

•

Suspended matter

The above tests are described within this manual and the tank cleaning manual. All wall wash tests have to be recorded on the corresponding form XX ‘Wall wash Test record’.


6.5.5


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VMS/CHM/01 01 4 of 16

Wallwash procedure This describes an approved method for collecting and analysing wall wash samples to determine the presence of contaminants on the bulkheads. The procedure involves contacting a constant area of the bulkhead with a given amount of specification grade methanol, collecting the liquid and analysing it for the presence of chlorides, hydrocarbons, colour and particulate matter, or whatever might be required by the Charterer. PRECAUTIONS •

Safety Considerations – eye protection is required when collecting the samples to prevent the inadvertent contact of methanol with the eyes during the sample collection process. Gloves should be worn to prevent the absorption of methanol into the skin.

•

Disposable plastic gloves are also worn to prevent contamination of the samples during the collection process. (A sufficient amount of chlorides can be absorbed from the skin to cause the sample to fail the chloride analysis.)

•

Chlorides are abundant in the marine environment. All sampling equipment including bottles, funnels and other apparatus must be thoroughly rinsed with methanol (of less than 0.2 ppm chlorides content) and stored in plastic containers. Bottles are to be capped prior to sample collection.

•

Personnel collecting the samples must be certain that no perspiration or bare skin contacts the sample or sampling equipment while the wall washes are being collected.

CHOICE OF TEST SITES •

As a minimum, four sites of approximately 1.2 square feet each must be chosen in each tank. (If additional sites are chosen, 100mls of methanol should be applied to each location and collected in a separate container.)

•

Any area that appears to have crystalline deposits should definitely be tested.

•

Separate test of non-typical areas greater than 2 square feet (discoloured patches etc.) should be conducted. The sample collected should be labelled with a description of the nontypical area. (These areas should be analysed separately.)

SAMPLE COLLECTION PROCEDURES Choose four surfaces to test. Using the plastic wash bottle, squirt methanol on the test section at the highest practical point (normally 1.5 up to 2 metres) above the tank bottom in a stream of about 10cm wide. Allow the methanol to run down the wall approximately 15 cm and begin collecting it with the funnel, squirting additional liquid as necessary to rinse the flushing into the sample funnel. Continue this process until approximately an area of 10 by 120 cm has been rinsed with 100 mls of methanol. After the washings from the four sites are collected, submit a portion of the sample for analysis of chlorides, colour, suspended matter and hydrocarbons, whatever is applicable. The accuracy of this test depends upon consistency. • •

Consistent number of sites tested. Consistent area tested at each site.


• •


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VMS/CHM/01 01 5 of 16

Consistent amount of methanol applied to each site. Consistent amount of methanol recovered from each site.

For the purpose of standardising methods and maintaining the desired consistency; the following criteria have been established: Four wall wash sites. • • •

An area of 10 by 120 cm for each wall wash. 100 mls of methanol applied to each site. 250 mls total minimum recovery of methanol (approximately 60% of each of the four 100 ml washings).

EQUIPMENT AND REAGENTS • • • • •

6.6

Polyethylene washing bottles, 500 ml capacity Bottles, glass with screw cap and polyethylene lined, of sufficient capacity to hold the washings. Plastic disposable gloves. Specification grade methanol (laboratory pure methanol) that has been tested to be less than 0.1ppm chloride by ion chromatography. (High quality methanol is vital to the accuracy of this test.) Sample funnel, plastic or stainless steel with one flat side that can be held flush with the bulkheads.

VESSEL - SURVEYOR AGREEMENTS The surveyor determines the ship’s readiness for loading. Depending on the previous cargoes and the cargo planned for the tank, he will carry out either a visual inspection of tanks and lines or add additional tests such as odour, wall wash etc. Once the tanks are approved a ‘cleanliness certificate’ will be issued by the surveyor. The surveyor will ask the vessel the following information: • • •

‘Last 3 cargoes’ carried in tanks to be loaded Information on tank cleaning Ship experience factor

Prior commencement of loading Chief officer and Surveyor will discuss the loading programme.

6.7

CARGO SAMPLING

6.7.1

General Cargo samples are evidence of the condition of the product during the various phases of transport (storage at terminal, arriving on board, loading, passage, discharging). This procedure describes sample-taking procedures and the legal background.



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VMS/CHM/01 01 6 of 16

Depending on the cargo involved, a series of samples are taken to determine the ship’s preparedness for loading. How many samples are taken depends on the conditions in the charter party and the type of cargo. Unless specified otherwise, as a general rule a sealed sample should be taken for every tank carrying cargo. Samples taken by the vessel bearing no signature from the surveyor or other authorised person, unless a very good documented sample log is kept by the vessel, have no real value as evidence in legal actions. Samples must be taken at the manifold prior to releasing cargo to the tanks to ensure that Shippers lines are clean. 6.7.2

Safety Sampling is risky, vapours or spray from the product may cause poisoning, caustic burns or scalding of personnel. Release of small amounts of products may also cause problems on deck or the environment (terminal, water). For these reasons, it is absolutely necessary to comply with the strictest safety regulations and the requirements of the material safety data sheets. When samples are taken through tank openings (hatches), personnel should stay to the windward side of the opening. Depending on the properties of the cargo, suitable protective clothing should be worn as required. When taking samples from lines under pressure the risk of spray from the product should be taken into account. Sampling should not take place until 30 minutes after loading has been completed to ensure any static charges have been dissipated.

6.7.3

Labels The labels of the cargo samples must at least contain the following information: • • • • • •

6.7.4

Name of the vessel Port of loading Cargo Tank Date and time Signature from surveyor and Chief Officer.

Storage of samples All samples that remain on board are to be properly stored in the designated sample locker. Storing samples even for brief periods, in rooms or places not intended for this purpose (i.e. cargo office) is prohibited. In general samples can be disposed off two months after discharge of the cargo, unless: •

There is a cargo claim, or

•

There are special instructions from Charterers.


6.7.5


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VMS/CHM/01 01 7 of 16

Sampling on land Samples from the land tank and line are always taken by the independent surveyor, without a ship’s representative being present.

6.7.6

Sampling on board Sampling on board should always be witnessed by an officer.

6.7.7

Sampling cargo under nitrogen blanket In case of cargoes loaded and transported under permanent nitrogen blanket, the samples must not be taken through tank openings, since otherwise the moisture and/or oxygen in the air might react with the cargo. Sampling can only be done by means of a suitable valve and pumping around or with help of the closed sampling device. All safety regulations applicable for the situation and the cargo must be complied with.

6.7.8

Release of samples to third parties Samples must only be released to third parties under direct instructions from Charterer’s and/or Management Office and a detailed receipt has to be obtained for each sample. Sample log to be updated. Samples relating to a cargo claim may only be handed over to a representative of a P&I Club and after getting a receipt for the same.

6.7.9

Disposal of samples Samples should only be disposed of to approved shore reception facilities.

6.7.10 Sampling programme A complete sampling programme consists of the following elements: •

Sample from the land tank/line

•

Manifold sample

•

Sample from the ship’s line and/or pump stack.

In the latter case the valve(s) to the tank i.e. drop-valve and delivery remain closed. •

First Foot sample

At least enough cargo should be in the tank to fill a sample bottle. ‘First Foot sample’ refers to filling the tank approximately at one foot innage level. However, with solidifying cargo such as phenol sufficient cargo should be in the tank to cover the total length of the heating coils. Line flushing



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VMS/CHM/01 01 8 of 16

If a product is to be loaded into several tanks, either a certain amount of cargo is transferred from tank to tank until in the last a foot sample can be taken, or all tanks will receive ‘one foot’ cargo. Circulation rinsing with product may be required to wash lines Washing of tanks using re-circulated cargo to obtain satisfactory samples is not to be undertaken without direct management office approval and special safety precautions.

6.8

PRE-LOADING MEETING

6.8.1

GENERAL This procedure describes the main points to be discussed on arrival before loading operations can start. The complexity of loading/discharging operations on chemical tankers makes it necessary to plan all activities in which vessel and terminal are involved. Parties: • • •

Terminal Vessel Expert

Loading master Master/Chief officer Surveyor.

The surveyor is present as an independent expert commissioned by the shipper and plays an important role in tank inspection and cargo analysis. The agreements between the parties are put in writing. 6.8.2

Vessel –terminal agreements The Master/Chief officer should present the Notice of Readiness (NOR) to the loading master for his signature. The loading master is the addressee for all protests in connection with loading. The ChiefOfficer and loading master will discuss the loading programme. All relevant items, in the ‘Ship/Shore Safety Checklist’, should be checked by loading master and Chief Officer. After agreeing both must sign. Occasionally the loading master will ask for the Certificate of Fitness and/or hose certificates as applicable. Agreements specific to the ship and the cargo are to be made. Depending on the particular situation this may include: • • • • • •

End of loading- Ship stop/shore stop Loading rate (m3/h) Closed loading procedure Quantity to be loaded including options Topping off procedure Cargo data: specific weight, ‘in air’ or ‘in vacuum’ correction factors - loading temperature - hazardous chemical data sheet for manufacturer


• • • • • •


: : :

VMS/CHM/01 01 9 of 16

Blowing of the loading lines as necessary Use of the vapour return if required Purging if required Blanketing with nitrogen if required Port and terminal regulations, nautical warnings and information In case several parcels are loaded through the same line, binding order and sequence of loading.

The loading master must also issue the following documents: • •

Heating instructions from the shipper Inhibitor certificate (for monomer cargoes).

6.9

PREPARATION BEFORE CARGO LOADING

6.9.1

General Before cargo loading starts, the responsible officer should be satisfied that the precautions set out in chapter 3 are being observed. The appropriate checklists shall be utilised. Pre cargo loading meeting shall be carried out between ship and cargo shipper as detailed above.

6.9.2

The following important pre-loading checks are to be made by the ship: •

Product characteristics must be known, including compatibility with other cargoes, heat sensitivity, risk of exothermic self-reaction, toxicity and general safe handling practices.

•

Normally tanks to be loaded are pre-inspected for cleanliness by independent surveyors. The responsible officer should satisfy himself that the tanks to be inspected are well ventilated and safe to enter (VMS/SEM/01 4.6.8). The surveyor must be accompanied by the responsible officer or a person delegated by him.

•

Tanks passed for loading should be tightly secured with all cargo openings closed.

•

Tank instrumentation (level gauges, level alarms, thermometers etc) must be tested for operation and accuracy.

•

Remote valve closing devices, cargo pump/line pressure gauges must be checked and tested.

•

Cargo lines and crossovers to be inspected and all drain plugs closed and secured.

•

Cargo manifolds should be ready for shore hose connection with only the connecting side end blank removed and tagged with tank name and product to be loaded.

•

Fire protection equipment must be inspected and ready for immediate use.

•

Protective clothing and breathing apparatus are being worn or are immediately available as necessary.



: : :

VMS/CHM/01 01 10 of 16

The following ship - shore checks are necessary: •

Local and terminal regulations have been received in writing and are being observed

•

Agreement has been reached with the responsible terminal representative about: •

signals to indicate “stand by”, “start operation”, “slow down”, “stop operations “

•

pumping rates

•

pumping and loading sequence

•

action to be taken in case of fire or other emergency

•

emergency shutdown procedures.

•

access to the ship, and smoking restrictions

•

sampling procedure, could include manifold, pump stack and foot samples and will they be running or require stops. Will lines be popped with N2 prior to loading.

•

a ship-shore bonding connection, if used, is made before hoses are connected, and if an insulating flange is used, its insulation has not been impaired.

•

cargo-hoses, loading arms and gaskets are suitable and certified for the intended cargo and are in good condition. Flexible hoses should be suspended by suitable equipment and not subjected to excessive bending or put excessive strain on the cargo manifold. Mechanical loading arms must be supported in a way that they do not put excessive force on the manifold. Care should be taken to protect mechanical manifolds from mechanical damage. The ship’s own cargo hoses should not normally be used for shore connection and in case they are used, they must be tested and certified as per regulation in the IBC code and LOI received. Also check they are compatible with products to load and are clean

•

before commencing loading the responsible officer must ensure that the cargo lines are set in the correct loading mode, and that cargo venting system is set as per regulation, i.e. open, restricted or closed.

•

certain cargoes require vapour return to the shore facility. The responsible officer must ensure that the shore and ship vapour system are compatible and that the system is operated in compliance withthese procedures, local and terminal regulations.

6.10 CLOSED LOADING OPERATIONS 6.10.1 Purpose and scope This procedure describes the requirements for closed loading operations. The Master has overall responsibility for compliance with closed loading procedures. Closed loading has to be carried out as a requirement of the:



: : :

VMS/CHM/01 01 11 of 16

•

IBC/BCH Code. The IBC-code does not use the term ‘closed loading/unloading’ explicitly but mentions controlled venting and restricted or closed gauging.

•

Company procedure

•

Contractual obligations

•

Port/ National requirements

6.10.2 Company procedure Vessels equipped with a system such as Skarpenord (pressure gauges in the tanks) or radar ullage systems shall at all times carry out closed loading/unloading procedures for all cargoes. The above means loading or discharging with securely closed ullage, sounding and sighting ports. Additionally the venting must be controlled. For gauging e.g. ullaging, sounding and sampling closed devices must be used. The level alarm systems must be operated during the entire closed cargo operation. Closed cargo operations must be stopped as soon as any essential system for safe loading or discharging becomes inoperative. 6.10.3 Gauging, sounding and sampling A closed gauging device penetrates the cargo tank, but is part of a closed system and prevents the cargo or its vapour being released. Examples are the float-type systems, radar systems, electronic probe, magnetic probe and protected sight-glass. For sampling and sounding the Dovianus or Hermetic systems may be used. 6.10.4 Cargo tank venting Controlled venting must be established if closed cargo operations are required. A controlled tank venting system is a system with pressure and vacuum-relief valves (P/V-valve) fitted on each tank in order to limit the pressure or vacuum in the tank. The P/V valve should operate in such a manner that neither pressure nor vacuum is created in the cargo tank during cargo operations that exceed the tank design parameters. 6.10.5 Vapour return Vapour return should be used in accordance with local, terminal or customer’s requirements. Very toxic and volatile cargoes should, if the shore is equipped with a vapour return, be loaded/unloaded with vapour return in order to avoid vapour release into the atmosphere. 6.10.6 Customers’ requirements Specific closed cargo operations may be required by the customers under the charter party or Contract of Affreightment (COA). The management office will inform the Master when such requirements exist.



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VMS/CHM/01 01 12 of 16

6.11 LOADING OPERATIONS 6.11.1 General This procedure describes the commencement, carrying out of loading operations and the final loading measures from disconnecting of the loading derrick/hose to making ready for sea voyage. 6.11.2 Commencement and execution of loading Immediately prior to commencing loading the valve setting and the lines on all tanks have to be checked once more. The responsible officer must be satisfied that the cargo system is, in all respects, ready and all the information of the cargo has been received. The following precautions must be observed: •

the quantity of the cargo to be loaded has been agreed to

•

the loading rate has been agreed to

•

shore or ship stop has been agreed to

High and high/high level alarms MUST be in operating position Loading must start at a low rate. In this stage the cargo line, manifold, connections, drain points etc. must be checked for leakages. The full loading rate should not commence before both ship and shore are satisfied that there is no leaks in the system. When all is ok shore can be informed to increase the loading rate to the agreed level. During the loading at least one deck officer must be on duty and available at all times. At least one crewmember must be on deck/manifold throughout the cargo operation. The officer on duty is obliged to carry out the loading in accordance with the instructions received from the Chief-Officer, which should at least encompass the agreements made with the Loading Master as well as the Surveyor. Some cargoes loaded in hot climates are chilled and cause bulkheads to sweat on loading. Consideration must therefore be given to sequences of loading. During the whole loading a detailed cargo log has to be kept. Sufficient ullage space should be maintained after loading to allow for heating cargo as required by the Shipper. Loading one product in more than one tank simultaneously may increase the risk of an overflow, and the responsible officer must ensure that tanks that are “topped off” are properly isolated from tank(s) still being loaded. When nearing completion of loading the shore should be notified and the loading rate reduced 6.11.3 Completion of loading and final measurements When loading is completed the final loading measurements have to be carried out. In order to make the derrick/hose and vessel’s cargo line free from product, the lines are blown from the shore. Cargo



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VMS/CHM/01 01 13 of 16

sensitive to Oxygen is given a nitrogen blanket following loading. The surveyor together with an officer will take the ullage and cargo temperature of the tank(s) concerned. In the presence of an officer cargo samples are taken sealed and labelled. •

upon completion of loading the manifold valve must be closed

•

in cases were the shore line is emptied by either “blowing” or “pigging” the product into the ship tank(s) the responsible officer must ensure that the tank(s) have sufficient space to accommodate the quantity in the shoreline.

•

“blowing” or “pigging” can cause a pressure surge and the responsible officer must monitor this operation carefully in order not to over-pressurise or overflow the tank.

•

during customary ullaging and sampling the responsible officer must ensure that that this activity is conducted as per local and/or international regulations and that proper personal protective equipment is used.

•

disconnecting of shore hoses or arms must only take place after they have been drained for cargo residues and relieved of any pressure after blowing/pigging.

•

personnel engaged in hose disconnection must wear proper personal protective equipment.

•

Cargo heating system should be tested as required.

•

Cargo cooling system should to be tested as required.

6.11.4 Blowing lines The loading line is always blown through with either compressed air, steam or nitrogen, depending on the cargo, to empty it between manifold and terminal. This is necessary to ensure risk-free release of loading arm or hose connection. If possible the vessel’s line system used should also blown empty this way. With heated or solidifying cargoes this is a must. In case of high viscous cargo it is important to be aware that after blowing the cargo may contain an air-bubble and therefore the ullage measured immediately after blowing is less than it should be (Vegetable oils). Pre-blowing and after-blowing ullage measurements should give a good indication of this. The tank in question has to settle before a correct ullage can be taken. 6.11.5 Pigging At some installations the landline from tank farm to jetty manifold or part of it are pigged. It is possible that large amounts of cargo are pressed into a cargo tank at high rate and high pressure. Method and required tank volume necessary for this shoreline emptying must be agreed upon in the pre-loading conference. Especially one must be aware of the high pressure which could be created when pigging and take precautionary measures to prevent over-pressurising the tank or creating an overflow.



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VMS/CHM/01 01 14 of 16

6.11.6 Disconnecting of loading arm/cargo hose Before the loading arm/ cargo hose is disconnected the officer on duty must satisfy himself that no pressure is left in the arm or hose. Crew disconnecting should wear the appropriate protective clothing. If the drip tray under manifold is not large enough, especially when using reducing pieces, suitable containers should be made available. 6.11.7 Measuring Ullaging The surveyor together with the chief-officer will carry out the ullaging to determine the cargo volume of a loaded tank. With closed loading the appropriate equipment has to be used. The equipment (UTI) must be fully operational and clean. After determination of the ullage, the cargo volume is to be determined using the ullage tables, with the corrections for: •

Trim

•

List

•

Temperature (if required).

6.11.8 Measuring Temperature The temperature required can be established by using: •

Remote thermometer

•

UTI

•

Manual thermometer lowered into the cargo through the tank opening.

The thermometer used should be regularly checked by means of a calibrated thermometer. The delta T. °C. should be recorded and applied to if necessary on the temperature found. When remote thermometers are used, the number of measuring points is restricted to the number of built-in thermometers. Since differences of temperature may occur within the cargo several measurements should be carried out if possible, in particular for heated cargoes. The American Society for Testing Materials (A.S.T.M.) recommends to proceed according to the following table.(ASTM Standards Part 8.).

depth of

Minimum number of

product

measurements

> 15 ft

3

Measurements levels 3ft below surface

middle

3ft above bottom


10-15 ft

2

under 10 ft

1


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VMS/CHM/01 01 15 of 16

3ft below

3ft above

surface

bottom middle

6.11.9 Measuring Water In case of non-water soluble products that are lighter than water (e.g. lubricating oils) ullaging results may be falsified, in some cases, by considerable amounts of free water. For commercial reason it must be determined: Whether the cargo contains water How much water is in the cargo. Water detection (water dip) and water measurement methods are: •

Water finding paste

•

Interface detector(UTI)

A sample of any water in the cargo is taken with the aid of the bottom sampler to ensure that claims may be defended. The Master has to protest formally and/or the P&I club and the management office have to be informed, as required by circumstances. 6.11.10

Nitrogen cover

Some cargoes require a nitrogen blanket to prevent oxygen or moisture entering into the vapour space of the tank. The terminal is nearly always responsible for putting a blanket on top of the cargo. The maximum ‘blanket’ pressure corresponds with the P/V valve setting and is either 200 mbar or 600 mbar. The nitrogen blanket is put in place after completion of loading, ullaging, and temperature measurements. Manometers suitable for checking the blanket pressure are to be installed. Fixed pressure sensors have to be checked regularly using a calibrated manometer. Requirements to maintain the blanket are described in chapter 7. 6.11.11

Preparation for sea voyage

Cargo samples •

These are to be stored safely in the designated sample Storage elsewhere in cargo office or accommodation is not allowed.

Manifold •

The blind flanges on the manifold have to be fitted and fully bolted.

P/V Valves

store

/

locker.


•


: : :

VMS/CHM/01 01 16 of 16

The P/V valve setting should be in accordance with C.O.F.

Hoses •

All loading hoses, jumper hoses, have to be disconnected. If vessel’s hoses have been used, these hoses should be cleaned and thereafter fitted with blind flanges. Thereafter hoses are to be stowed for the sea-voyage.

•

Hoses on the vapour return line, between central vapour return line and specific tank in the towers, when applicable have to be removed. The vapour return line has to be fitted with blind flanges wherever applicable.

Tank alarms •

Tank alarm system to be switched off.

Tank closures and openings •

As far as they not closed already all tank hatches butterworth hatches etc. have to be checked that they are closed before commencing the sea voyage.

In general a round over deck should be made by a responsible officer to check that the cargo area is seaworthy in all respects.

CHEMICAL TANKER MANUAL SECTION 7 – CARGO CARE

7.

CARGO CARE

7.1



: : :


The following reference publications are to be read in conjunctions with this section:

7.2

Publication

Location

International Safety Guide for Oil Tankers and Terminals (ISGOTT)

Chief Officer

Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk

Master


Master

BCH/IBC Code

Master


7.3

Company Form No

Title

TNK 08

Cargo Heating Report

CARGO CARE REQUIREMENTS This section describes measures to ensure that the cargo remains on spec. in accordance with the requirements stipulated by the Charterer during the entire period on board the vessel. Care procedures for some specific cargoes are to be followed according to the cargo data sheets. Cargoes transported on a chemical tanker differ widely in characteristics and mode of handling, a fact that also needs attention during transit. Precaution/attention are necessary for cargoes that need: •

Cargo heating. Cargoes that require heating must be monitored at least daily and a temperature log must be kept. Ensure that correct heating medium is used, and that heating coils in tanks that do not require hating are blown dry and blanked. Prior to loading heated cargo heating coils should be pressure tested and results recorded in the log book.

•

Cargo Cooling. Cargoes that need cooling must be monitored daily and kept at the recommended temperature and a temperature log must be kept.

•

Temperature Control. Cargoes that may self-react must be monitored on a daily basis for any fluctuation in temperature that deviates from the ambient climatic conditions.



: : :


Certain cargoes may undergo polymerisation or decomposition. To prevent this from happening small amounts of chemical additive or inhibitors are introduced into the tank during the loading process. Inhibitor certificates should be referred to and Charterers instructions followed. The temperature of such cargoes must be monitored regularly whilst on passage and should temperatures be noted to rise independently then it must be assumed that the process of polymerisation has begun and the Company must be advised immediately. Once polymerisation has begun it is a rapid self-perpetuating process and can be extremely dangerous structurally. A significant example of such a kind of cargo is Styrene Monomer where the expansion ratio is 10 : 1 during the polymerisation process.

7.3.1

•

Nitrogen cover. Prior sailing the vessel must have sufficient Nitrogen of the correct quality on board to comply with the padding requirements.

•

Tank atmosphere – O2 content strictly controlled

•

Agitation/ Circulation

•

Other as defined by Shippers

Heating The voyage orders will contain heating information, if heating is required. As a rule the final heating instructions are given by the Shipper in writing to the Master / Chief Officer in the port of loading. If those written instructions are not given, the master should request them and issue a Letter of Protest if they are not received at departure. In the latter case the management office should be immediately informed. The heating instructions may contain any, or all, of the following: •

Minimum and maximum temperature during the voyage

•

Minimum and maximum temperature during discharge

•

Maximum temperature of adjacent cargo

•

Heating medium

•

Maximum temperature of the heating medium

•

The maximum possible temperature increase per unit of time: delta T°C/hour

Unintended heating The risk of heating a cargo, which should not be heated must be eliminated. An ‘unintended heating’ of a cargo can not only influence the quality of the cargo, but can endanger the crew, the vessel and the environment, e.g. lifetime of an inhibitor can be shortened drastically by unintended heating and a monomeric cargo such as styrene monomer can polymerise. In order to prevent unintended heating of cargoes that do not require heating the following preventive measures should be taken: •

Blank the supply and return of the heating coils


•


: : :


Check when heat is supplied to other tanks manually the supply and return of the tanks that do not require heating.

Heating required by Marpol Annex II Certain Category ‘B’ and ‘C’ products require as solidifying cargoes a prewash. However, outside special areas these cargoes do not require a prewash if the following is complied with: •

Cargoes with a melting point less than 15°C. Discharge temperature should be at least 5°C. above melting point of the product. Example: Benzene with a melting point of 4.5°C. should be discharged with a temperature of at least 9.5°C. to avoid the prewash requirements.

•

Cargoes with a melting point above 15°C. Discharge temperature must be at least 10°C. above melting point of the cargo. Example: Phenol, with a melting point of 40.9°C. should be discharged with a temperature of at least 51°C. in order not to be considered solidifying.

The Master has to obtain the applicable information when transporting such cargoes so that the products will be heated accordingly so as to avoid the prewash obligation if at all possible. Temperature checks When carrying heated cargoes the following parameters are to be checked regularly: •

Temperature of the cargo

•

Inflow temperature of the heating medium

•

Outflow temperature of the heating medium

The results as well as failures, if any, should be recorded in the ‘Voyage-Log’. 7.3.2

Cooling/Refigeration Cooling, in specialised cases, is required to prevent products from giving-off toxic and flammable vapours. Special care requirements are generally documented in the condition of carriage details contained in the ships Certificate of Fitness and also in the IBC/BCH Codes. The Company and Charterers are to be consulted if additional information is required.

7.3.3

Nitrogen blanket Some cargoes require a nitrogen blanket to prevent oxygen or moisture entering into the vapour space of the tank. Otherwise the cargo could react with the oxygen, moisture or salts dissolved in the air and become off-specification. A nitrogen blanket can only be maintained properly if: •

The pressure sensor or installed manometer is working correctly. (regular checking and calibrating throughout the year).



•

A permanent over-pressure is maintained.

•

The P/V valve shall be set accordingly.

•

The Vapour return line is disconnected

•

Tank openings are fully closed, (sealed with silicon, if necessary)

: : :


Tank leaks must be repaired immediately, as the amount of nitrogen on board is limited. Tank pressures have to be checked every four hours and recorded in the ‘Voyage log’. 7.3.3

Oxygen Some cargoes like Hexene-HMD-Octene do have a maximum requirement with respect to oxygen in the vapour space. The vapour space has to be checked with the appropriate oxygen meter. The Shipper determines the frequency of the routine checks. The results are to be recorded in ‘Voyage Log’.

7.3.4

Agitation/Re-circulation Some chemicals, e.g. Phosphoric Acid, require agitation to prevent separation and different temperature/density layers from forming. Re-circulating through a diffuser is one method of agitating the cargo.

CHEMICAL TANKER MANUAL SECTION 8 – PREPARATION FOR DISCHARGE AND DISCHARGING


: : :


8.0 PREPARATION FOR DISCHARGE AND DISCHARGING 8.1

REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section.

8.2

Publication

Location

International Safety Guide for Oil Tankers and Terminals (ISGOTT) Ship’s “Procedure and Arrangements Manual” (Approved by Class) Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk Ship to Ship Transfer Guide (Petroleum)

Chief Officer Master Master Chief Officer

COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Company Form No MAR 02 MAR 03 MAR 08 TNK 01 TNK 03 TNK 05 TNK 06 TNK 07 TNK 09 TNK 11 TNK 12 TNK 15

8.3

Title Port Log Notice of Readiness Cargo Loading and Discharge Plan Pre arrival and commencement of cargo operations checklist Completion of Cargo and Pre Departure Checklist During Discharge Operations Checklist Ullage Report Pumping Record Inert Gas Log ROB Report Dry Receipt Vessels experience factor (load)

PURPOSE AND SCOPE This section describes measures to be taken immediately before discharge and during discharging operations and special duties as well as procedures for the discharge of certain cargoes. Instructions to discharge cargo must only be accepted from the Company or Charterers. Instructions received from parties other than the above must be checked and confirmed with the Company or Charterers. Prior discharging the relevant tanks and associated discharging equipment must be checked for technical readiness.

8.4

TECHNICAL READINESS The following measures have to be taken prior discharge:


8.5


: : :


•

Switch on High – Level alarms. They should have been kept switched on during passage to give warning of any change in tank level due to cargo loss to ballast tanks

•

Prepare the Level gauging system

•

Check if P/V valves settings are according to the requirements

•

Prepare the vapour return line-if required.

•

Continue/reduce/close tank heating on relevant tanks

•

Prepare manifold, drip tray and cargo line system.

•

Manifold- reducer-ASA/Din

•

Prepare ballasting system

•

Prepare / check jumper hoses or fixed connections.

•

Check Nitrogen system

•

Check if all is ready for closed discharging

•

Set Decontamination shower and eye-wash in operational position

•

Check if relevant instruments are ready for use.

•

Prepare / post cargo description

•

Prepare discharge plan

•

Ensure cargo temperature in accordance with receivers requirements

SAFETY Post stowage plan, cargo operation forms and chemical hazard data sheet/MSDS. Brief crew on the following:

8.6

•

Risk level of the cargo(es) to be discharged

•

Chemical protective clothing to be worn, when dealing with the cargo

•

Fire fighting equipment to be used

•

What to be done in case of spillage

•

Additional medical equipment

ULLAGING AND SAMPLING The cargo surveyor will check together with the chief-officer the ullages of the tanks to be discharged. Cargo sampling by the surveyor must be conducted in presence of an officer. The method used for calculating specific density at the disport must be the same as the method used in the load port.


8.7 8.7.1


: : :


PRE-DISCHARGE MEETING General This procedure describes the main points to be discussed on arrival before discharging operations can start. The complexity of discharging operations on chemical tankers makes it necessary to plan all activities in which vessel and terminal are involved. Parties: •

Terminal

Loading master

•

Vessel

Master/Chief Officer

•

Expert

Surveyor.

If for any reason it is assumed that any party is planning to file a claim of any kind against the vessel the cargo samples from the loading port are to be retained on board. They may only be given to persons stipulated after consultation with the management office. 8.7.2

Vessel –terminal agreements The Master/Chief officer should present the Notice of Readiness (NOR) to the loading master for his signature. The loading master is the addressee for all protests in connection with the discharging. The Chief-Officer and loading master will discuss the discharge programme. All relevant items, in the ‘Ship/Shore Safety Checklist’, should be checked by the loading master and the chief-officer. After agreeing both must sign. Occasionally the loading master will ask for the C.O.F. and/or hose certificates. For chemicals which, according to MARPOL Annex II, are subject to the prewash obligation the washing programme and slop disposal are to be agreed upon.

8.7.3

Vessel - surveyor agreements The surveyor has to discuss with the Chief Officer the discharging and sampling programme, especially if the cargo is kept under a nitrogen blanket. The surveyor receives the cargo samples destined for the receiver from the port of loading in exchange for a receipt.


8.8

CLOSED UNLOADING OPERATIONS

8.8.1

General


: : :


This procedure describes the requirements for closed unloading operations. The Master has overall responsibility for compliance with closed unloading procedures. Closed loading has to be carried out as a requirement of the:

8.8.2

•

IBC/BCH Code. The IBC-code does not use the term ‘closed unloading’ explicitly but mentions controlled venting and restricted or closed gauging.

•

Company procedure

•

Contractual obligations

•

Port/ National requirements

Company procedure Vessels equipped with a system such as Skarpenord (pressure gauges in the tanks) or radar ullage systems shall at all times carry out closed unloading procedures for all cargoes. The above means loading or discharging with securely closed ullage, sounding and sighting ports. Additionally the venting must be controlled. For gauging e.g. ullaging, sounding and sampling closed devices must be used. The level alarm systems must be operated during the entire closed cargo operation. Closed cargo operations must be stopped as soon as any essential system for safe loading or discharging becomes inoperative.

8.8.3

Gauging, sounding and sampling A closed gauging device penetrates the cargo tank, but is part of a closed system and prevents the cargo or its vapour being released. Examples are the float-type systems, radar systems, electronic probe, magnetic probe and protected sight-glass. For sampling and sounding the Dovianus or Hermetic systems may be used.

8.8.4

Cargo tank venting Controlled venting must be established if closed cargo operations are required. A controlled tank venting system is a system with pressure and vacuum-relief valves (P/V-valve) fitted on each tank in order to limit the pressure or vacuum in the tank. The P/V valve should operate in such a manner that neither pressure nor vacuum is created in the cargo tank during cargo operations that exceed the tank design parameters.


8.8.5


: : :


Vapour return Vapour return should be used in accordance with local, terminal or customer’s requirements. Very toxic and volatile cargoes should, if the shore is equipped with a vapour return, be loaded/unloaded with vapour return in order to avoid vapour release into the atmosphere.

8.8.6

Customers’ requirements

SPECIFIC CLOSED CARGO OPERATIONS MAY BE REQUIRED BY THE CUSTOMERS UNDER THE CHARTER PARTY OR CONTRACT OF AFFREIGHTMENT (COA). THE MANAGEMENT OFFICE WILL INFORM THE MASTER WHEN SUCH REQUIREMENTS EXIST.

8.9

DISCHARGE

8.9.1

General The general precautions in section 3 are to be observed prior to and during discharge. Particular attention should be paid to ships cargo discharge equipment, such as pump, pump room ventilation etc. The following precautions should be observed :

A pre-discharge conference with responsible terminal personnel which should include •

characteristics of cargoes to be discharged

•

sequence of cargoes to be discharge

•

temperature of cargoes to be discharged

•

quantities of cargoes to be discharged

•

pumping rates and pressure

•

emergency shut down

•

mode of communications

•

careful monitoring of discharge temperature to ensure cargoes are not damaged due to over heating or lack of heat

Prior commencing discharge the responsible officer must ensure that the entire discharge system, including pumps and vents, are secured and ready. After completion of discharge, including stripping and line clearing to shore (never allow shore to drain lines and hoses back into a ship tank) personnel engaged in hose disconnection must wear proper personal protective equipment. All tank openings to be closed and secured. 8.9.2

Discharging agreements Prior to discharge the ship / shore checklist has to be completed by the chief officer and the loadingmaster. Thereafter they have to agree on the discharge plan. This discharge plan must be completed in writing and approved by the Master. As a minimum the discharge plan must at least contain the following information:


•

Manifold connection to be used for each cargo

•

Which tanks are to be discharged

•

Maximum discharge rate and/or back-pressure


: : :


The chief officer and the Loading Master shall both sign the discharge plan. Should the loading master refuse to sign, a letter of protest must be issued. The loading master will receive one copy of the discharging plan.

a) Commencement and execution of the discharge Before commencement of discharge the cargo pump emergency stop trips are to be tested. The Chief officer is once again to personally check that the correct line up of valves has been made and that all required isolations by spools or spectacles are made. Discharge should start at slow speed. During this phase the cargo line(s) should be examined for signs of any leakage. After confirmation from shore the discharge rate can be increased up to the agreed maximum or maximum backpressure. When several tanks containing the same cargo are connected i.e. by jumper hoses the risk of causing an overflow due to wrong setting of the valves is increased. In this case the level of the other connected tanks should be continuously monitored. Level alarms must be switched on. The officer on duty must be available throughout the cargo operation. One watchman it to be on deck in the vicinity of the manifold throughout the entire operation in order that any potential risk is identified immediately and the required steps are taken to promptly control or remedy the risks, such as but not limited to informing the officer on duty etc. The discharge must be conducted in accordance with the agreement made between the Chief Officer and the Loading master as well as additional instructions / standing orders given by the Chief Officer. 8.9.4

Pumproom precautions During the discharge the following, must be checked and complied with:•

Pumproom(s) ventilation to be in operation throughout.

•

The pumproom(s) is to be checked for leaks at least hourly during the discharge. In order to limit and minimise personal exposure to possible toxic hazards, personnel entering pumprooms for these routine hourly inspections are to be rotated. Personnel entering pumprooms are to make use of personal gas monitoring equipment provided on board.

The pumproom(s) is to be monitored for hydrocarbons and other possible toxic hazards.



: : :


8.10 MEASURES TO BE TAKEN FOR SPECIAL CARGOES 8.10.1 Ballast and heated cargoes The ballast tanks underneath a cargo tank with heated cargo should not be used for ballast and trimming purposes until the tank has been discharged entirely, otherwise the cargo temperature above the tank floor may drop below the melting point before discharging is completed. This may lead to solidification of the cargo on the tank floor and pumpwell, which increases the amount of residue as well as increasing cleaning. 8.10.2 Discharging cargoes under nitrogen cover Many cargoes carried under nitrogen cover must be discharged using vapour-return-lines. The tank pressure must be in excess of atmospheric pressure throughout the whole discharge period to prevent ingress of air i.e. oxygen. 8.10.3 Discharge of high viscosity products Prior to the discharge of highly viscous mineral or vegetable oils, agreement must be reached with the terminal as to whether the cargo can be pushed towards the pump well so as to keep the residue in the tank as low as possible. 8.10.4 Discharge of cargoes with high melting points Prior to discharge of cargoes with high melting points it is advisable to arrange for “Tank Dry” acceptance on a tank by tank basis with the surveyor. Once a tank has been accepted as being dry a small amount of water can be taken in to wash the pump. 8.10.5 Efficient stripping in accordance with P&A Manual Each tank should be stripped in accordance with the procedure as described in the P&A Manual in order to minimise the residues. It is important that list and trim are in compliance with the list and trim as laid down the Marpol stripping procedure. The stripping procedure described in the cargo system instruction manuals are to be followed. On vessels fitted with hydraulic systems and submerged pumps, stripping is achieved with the cargo pumps. Final draining of the tanks is accomplished by careful control of the cargo pump. The pump discharge line is cleared by purging the pump and discharge line with inert gas in the form of nitrogen. Air may be used with certain cargoes of a non volatile nature and which are not static accumulator cargoes. This procedure is described in the pump instruction manual. Make sure that the cargo residues in the hose connection between ship and shore are not blown back into the ship’s cargo lines. 8.10.6 Before loading arm disconnection Before disconnecting the loading arm from the manifold, the Master must be sure that the following checks have been carried out:



: : :


•

The line and the manifold reducer have been blown and they are empty and drained

•

The drain valve has been opened to drain any small residues remaining in the manifold connection.

8.10.7 Prewash according to MARPOL Annex II Following discharge of Category ‘A’ substances or highly viscous or solidifying Category ‘B’ or ‘C’ substances the tanks previously containing this cargo should be prewashed before the vessel leaves port in accordance with the P&A Manual. The prewash slops must be disposed of in the port of discharge. A receipt for the disposed slops must be received and appropriate entries must be made in the cargo log and in the cargo record book.

CHEMICAL TANKER MANUAL SECTION 9 – INERTING AND GASFREEING OF CARGO TANKS


9.

INERTING AND GASFREEING OF CARGO TANKS

9.1


: : :


The following reference publications are to be read in conjunction with this section: Location

Publication IMO – Inert Gas Systems Ship’s “Inert Gas Systems Instruction Manual” (Approved by Class) Ship’s “Procedure and Arrangements Manual” (Approved by Class) International Safety Guide for Oil Tankers and Terminals (ISGOTT)

9.2

Master Master Master Chief Officer


9.3

Company Form No

Title

TNK 09 SAF11

Inert Gas Log Enclosed Space Entry Permit

POLICY The Company considers that the continuous availability of inert gas and its correct use is of paramount importance. The cargo spaces and slop tanks are to be kept fully inerted in accordance with the requirements BCH/IBC Code and where required by the particular products/chemicals carried. If entry is required the space will be thoroughly cleaned whilst using inert gas. After cleaning the tank atmosphere must be purged with inert gas to reduce the hydrocarbon levels to less than 1.4% by volume to prevent the atmosphere from entering the flammable range during venting. The Tankscope is used for this purpose. The space must then be vented with fresh air ensuring that the space has not less than 20.8% of oxygen, not more than 1% LEL Explosimeter reading and that the concentration of toxic vapours less than the TLV before entry is made. The Master must ensure that the oxygen content of the inert gas supply in the main line to the tanks is not more than 5% by volume, at any required rate of flow. Code requirements, cargo requirements and local regulations may require the vessel to operate to a lower limit. If for any reason, the inert gas system cannot be operated, or the oxygen content of the inert gas supply cannot be reduced to below the required O2 level, or the level required by the local port regulation, the Master must consider stopping operations.



: : :


The Chief Engineer Officer is responsible for the maintenance of the Inert Gas Plant / Inert Gas Generator. It is the responsibility of the Chief Officer to measure the oxygen content of the Inert Gas main supply and the oxygen content in the cargo spaces. The Chief Officer is also responsible for the setting of valves on deck and in the pumproom (as applicable). In addition to the shipboard PMP an inert gas operations and maintenance log is to be maintained for recording of all required checks and tests and operational parameters of the IG plant and related equipment. It is the Company’s policy that oxygen levels in the inerted gas spaces must be maintained at not more than 7% by volume oxygen unless local regulations require a lower figure. For certain sensitive chemicals, for purity or safety reasons, the use of standard ships generated inert gas is not suitable. In some cases therefore the cargo containment will be prepurged with N2 and the cargo kept under a N2 blanket. In other cases Charterers may require tanks to be left without being inerted. In the event of any doubt about product property and whether or not inerting is required the Company are to be consulted for guidance and further instructions.

9.4

INERTING/PURGING The term inerting/purging generally refers to the replacement of air in a cargo tank by an inert gas, in chemical tankers most often by nitrogen, in order to prevent the formation of flammable vapours, oxygenation of the product, reduce humidity in the tank and/or protect the quality of the cargo. Cost and time spent, on inerting/blanketing, are usually paid by the Shipper. Vessels must be clear regarding the most efficient and cost effective method of completely purging their vessel. Maintenance of the nitrogen cover during the voyage is usually responsibility of the vessel. The extent of purging will normally be laid down by the BCH/IBC codes or by the cargo shippers. Inerting/purging is normally done by Nitrogen supplied from shore and the procedure should be part of the pre-loading checklist with special emphasis on;

9.5

•

tanks to be purged shall be locked-out/tagged-out with a special “no entry” tag

•

ship/shore to agree on the inert gas rate of supply in maximum standard cubic meter per minute (m3/min)

•

tanks to be inerted must have sufficient hatches/vents open in order to avoid overpressurising the tank and the tank pressure must be monitored.

BEFORE USE OF SHIPBOARD GENERATED INERT GAS The inert gas system must be available for use at all times. To ensure its availability it must be operated, tested, and maintained at regular intervals, and in accordance with the vessels Planned Maintenance System. The stock of spare parts carried must be maintained at the appropriate level and whenever critical parts are used they must be re-ordered immediately. All inert gas safety systems must be checked before use to ensure that correct operation is possible when required. These tests are described in the Inert Gas Operations and Equipment Manual and the manufacturer’s instructions, and must also include the following:-



: : :


•

Oxygen monitoring equipment must be calibrated and alarm points checked, this includes both portable and fixed equipment.

•

Automatic shut-down systems and valves checked.

•

Deck seal alarms tested.

•

Non return valves should be checked.

•

Hydrocarbon gas detectors should be checked and alarms tested.

•

Dryers, dew point meters etc. where fitted are maintained and calibrated.

An inert gas maintenance record is to be maintained during all above checks and testing.

9.6

FAILURE OF THE INERT GAS SYSTEM In the event of failure of the inert gas system or supply, action must be taken immediately to prevent air from being drawn into the tanks. All cargo and/or ballast pump operations must be stopped and the deck isolating valves for the inert gas system closed. Immediate action must be taken to repair the system. It is essential that the Company be informed immediately of such a failure together with the reason for failure if known, and of any spares that are required to repair the system. Masters are reminded that national and local regulations may require the failure of an inert gas system to be reported to the harbour authority, terminal operator and to the port and flag state administrations. On chemical carriers where a failure cannot be immediately repaired, discharge or tank cleaning may only be resumed if an external supply of inert gas is provided or the following precautions are taken, where permitted by the BCH/IBC Code, local regulations and by the particular products/chemicals carried :•

Flame screens are checked to ensure they are fitted and in good condition.

•

Valves on the vent mast risers are opened.

•

No dipping, ullaging, sampling or other equipment is to be introduced into the tank unless essential to the safety of the operation. If it is necessary for such equipment to be introduced into the tank, it is to be carried out only after at least 30 minutes has elapsed since the supply of inert gas to the tank has ceased. All metal components of any equipment to be introduced into the tanks must be securely earthed. This restriction is to be applied until a period of 5 hours has elapsed since the supply of inert gas into the tanks has ceased.

•

Company permission has been granted.



: : :


If it becomes necessary to clean tanks which have contained flammable cargo while the inert gas system is out of operation, the precautions detailed in the ISGOTT Guide must be observed. Should a vessel experience a partial failure of the inert gas system during discharge of cargo and the vessel is unable to supply sufficient inert gas to keep the tanks inerted at a positive pressure of at least 100mm water gauge, then the cargo discharge rate must be reduced to a level at which a positive pressure of 100mm water gauge can be maintained.

9.7

MAINTENANCE Vessels which are fitted with an inert gas system must carry out the routine inspections, tests and maintenance required by the vessel’s “Inert Gas System Operation and Equipment Manual”.

9.7.1

Deck Seal Inspection of a deck seal is to include the following:-

9.7.2

•

Opening of the unit for internal inspection.

•

Checks for blockages and condition in the venturis of semi-dry type seals.

•

Checks for corrosion or cracks in the inlet pipe and housing.

•

Checks for corrosion of the heating coils.

•

Checks for corrosion or damage to any of the internal parts of the seal or of the casing.

•

Inspection of Filters/Demisters.

P/V Breaker If the P/V Breaker is of the liquid type. Inspection of the P/V breaker is to include the following:-

9.7.3

•

Ensure gauge glass intact, clean and level visible (If fitted).

•

Check correct liquid used and the level is maintained for the density of liquid used.

•

If freezing conditions are expected, check the liquid used is suitable for low temperature use, if necessary anti-freeze is to be added.

Inert Gas Scrubber Inspection of the inert gas scrubber may be made through the access cover or manholes. Checks must be made for corrosion, fouling and damage to:•

Scrubber shell and bottom.

•

Cooling water pipes and spray nozzles.


9.7.4


•

Float switches and temperature sensors.

•

Other internals such as trays, demister pads and linings.

: : :


Non Return Valves Non return valves must be opened for inspection to check for corrosion and also to check the condition of the valve seat and the free movement of the valve. The operation of the valve is to be tested in service.

9.7.5

Flue Gas and Recirculating Valves Flue gas and recirculating valves are to be “stroked” at regular intervals when the system is not in service to ensure that they remain free to operate over their full range. Maintenance of the Inert Gas System and other components located within the machinery spaces is the responsibility of the Chief Engineer.

9.8

GASFREEING

9.8.1

General A space is considered as “gas free” when the concentration of flammable gases in its atmosphere is less than 1% LEL, the concentration of toxic gases (including IG components) is less than the TLV and the Oxygen concentration is not less than 20.8%. The Chief Officer is to supervise gas-freeing operations. The gas freeing programme and the progress of operation must always be available to all concerned. Protective clothing, resuscitation and fire fighting equipment must be ready for immediate use. All doors, ports, windows are to be kept closed. The inerted space can be purged with fresh air using the inert gas fans or water driven portable fans. Careful readings of the tank atmosphere must be taken with the ship’s portable gas detection equipment throughout gas freeing operations. Through the earlier stages of the operation, hydrocarbon readings are to be taken with the Tankscope (hydrocarbons by volume) and during the completion of gas freeing with the Explosimeter or Draeger Multigas Detector tubes. Many vapours are heavier than air, and after they escape from the tank openings or vents they will tend to lie around the decks. With light wind (below 5 knots) flammable or toxic mixtures may not disperse and lie about at some distance from where they arise. These gases may be carried through openings into galleys, accommodation, deck lockers etc. or be drawn into machinery spaces. It should always be suspected, even after spaces have been cleaned and made gas-free that some cargo liquid or vapour or both may be released whenever pumps, cargo lines, valves, heating coils, etc. are opened up. Precautions must be taken against such releases. Due to the risk of air pollution, gas freeing operations must not be carried out within port limits without the express permission of the appropriate authority.


9.8.2


: : :


Gasfreeing Precautions •

Check what type of vapours are involved; they may be flammable, toxic, corrosive or a combination of the above.

•

Alert other non-essential crew including the engine room that gas freeing is to take place

•

Wind direction may cause vapours to enter accommodation spaces or engine room and necessitate proper precautions (i.e. at sea the vessel may have to be turned off the wind).

•

Portable ventilation equipment must be checked and fully operational

•

Personnel involved must wear personal protective equipment as necessary

•

Vapour must only be released through openings as stipulated in SOLAS

•

After gas freeing no tank entry must take place before the Enclosed Space Entry Permit (VMS/SEM/01 4.6.8) has been issued by the responsible officer and the tank has been “tagged” safe to enter.

CHEMICAL TANKER MANUAL SECTION 10 – CARGO AND BALLAST PUMPS


: : :


10. CARGO AND BALLAST PUMPS 10.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section: Publication

Location

Pump Manufacturers Instruction Manuals

Chief Officer


Master

10.2 GENERAL The function of any pump is to transfer liquid from one point to another and this involves the use of piping. Such a transfer in a tanker can be divided into two parts:•

The movement of liquid from the tank to the pump. This is a function of the pump and its installation design. These factors are beyond the control of the ship provided the design ratings of the pump are maintained.

•

The onward movement of the liquid from the pump to its destination. This is an area where the efficient operation of the pumps is essential if optimum results are to be obtained. The major factors influencing pumping performance are discussed below. The flow of liquid to and from the pump must be matched exactly and this requires the flow on the suction side to be equal or greater than the discharge rate of the pump. Where the flow to the pump suction falls below the pumping rate cavitation will occur with the possibility of loss of suction and pump damage.

Centrifugal pumps do not suck liquids. The only factors which cause liquid to flow to the pump are:•

Pressure acting on the surface of the liquid.

•

The height of the liquid level in the tank in relation to the pump suction.

Since no centrifugal pump can generate a total vacuum at its suction inlet, only a proportion of the atmospheric pressure can be usefully employed. Therefore, before a pump can operate satisfactorily, a certain pressure must exist at the pump suction and this is known as the required Nett Positive Suction Head.

10.3 PUMP DESCRIPTIONS 10.3.1 Centrifugal Pumps The centrifugal pump has for many years been the most suitable pump where a high pumping capacity is the most important factor. The size and cost of such a pump does not increase in proportion with the throughput, as it is not a positive displacement pump. It requires either the



: : :


provision of ancillary self-priming equipment for the removal of air in the system or a separate stripping system. In a centrifugal pump the motive force is provided by a rotating impeller which takes its suction at its centre and centrifuges the pumped liquid outwards to the casing discharge. The head generated is dependent on the diameter, blade angle and speed of rotation of the impeller. Flow rate is affected by the pressure in the discharge system and can fall to zero. Reverse flow through the pump can occur if a non-return valve is not fitted and operational on the discharge side of the pump. The correct and efficient use of centrifugal pumps requires the observance of certain basic operating principles. Guidance on these principles is given here however, as manufacturers may incorporate special design features to meet operational requirements, the information given here must be read in conjunction with the manufacturers operating instructions and on board procedures organised. The basic characteristics of a centrifugal pump are:• • •

Throughput varies with speed. Head varies as speed squared. Power required varies as speed cubed.

These relationships are subject to appreciable variation caused by the system in which the pump operates. 10.3.2 Positive Displacement Pump Unlike the centrifugal pump, the positive displacement pumps used in dedicated stripping systems are capable of a low suction pressure and the ability to pick-up suction without external priming. This type of pump includes steam reciprocating pumps and ‘screw’ type pumps. Both types are now mainly used for stripping tanks or as specialised cargo pumps. The suction and discharge valves of a positive displacement pump must always be open before starting the pump and must remain open until the pump is stopped. These pumps must not be operated in excess of their design speed and particular care must be taken to avoid these pumps overspeeding when they lose suction. Pressure relief devices must be checked at regular intervals to ensure their correct operation. 10.3.3 Submerged Pumps Submerged pumps are relatively common on chemical carriers. This type of pump is usually powered hydraulically and provides for a pump located in each tank. 10.3.4 Portable Submersible (Emergency) Pump Portable submersible pumps, are provided on chemical ships and other specialised liquid cargo carriers, for discharging cargo in the event of a main cargo pump failure. The pumps are usually hydraulically driven and lowered directly into the tank generally through a tank cleaning hatch. All necessary safety precautions relevant to the actual cargo being handled are to be observed and in all



: : :


such cases the company are to be informed and permission obtained from the local port authorities before operations are commenced.

10.4 STARTING AND STOPPING PUMPS When dealing with steam or electrically driven cargo pumps the following procedures are to be followed: •

The Duty Engineer must be given adequate notice of starting or stopping cargo pumps.

•

The pumproom is to be checked as soon as possible after any pump unit is started.

•

The pump casing is to be vented of air or gas and primed full of liquid before starting the pump.

•

Starting of steam driven centrifugal pumps is to be done in accordance with the manufacturers instructions, and to be closely monitored by the Duty Engineer.

•

Centrifugal pumps are not be run above minimum speed until the Duty Engineer is satisfied with the operating condition of the drive unit.

•

Steam driven centrifugal pumps must be started against a closed discharge valve. Once the pump is turning the valve should be opened gradually as the pump is brought slowly up to the desired operating speed.

•

Electrically driven centrifugal pumps which run at constant speed, are to be started against a closed discharge valve. Once the pump is running the discharge valve is to be opened until the desired discharge pressure is achieved.

•

The stopping of steam driven centrifugal pumps must be carried out by the Duty Engineer, however, routine stopping may be carried out using remote controls providing prior notice has been given to the Duty Engineer.

•

The stopping of electrically driven pumps may be carried out from the Cargo Control Room. Before stopping the pump the load on the pump is to be reduced by closing in on the discharge valve. The Duty Engineer must always be advised of when such a pump is being stopped to allow him to monitor the generating plant as the electrical load changes.

10.5 EMERGENCY STOPPING OF PUMPS The emergency stopping of cargo pumps must be carried out by whatever controls are most accessible. All personnel involved in the cargo operations must be aware of the location of cargo pump emergency trips/stops.

10.6 CONTROL AND OPERATION OF CENTRIFUGAL PUMPS During operations consideration must be given to the prevailing suction and discharge conditions in relation to the pump’s performance characteristics. This is particularly important when operating cargo pumps where the rated capacity is achieved at a relatively high total head. Operation of these pumps with a low total head can grossly exceed the pumps rated capacity and cause excessive liquid velocities in piping systems.



: : :


10.6.1 Discharge Valves Control of a centrifugal pump can be achieved by either adjusting the pump discharge valve and/or restricting the pump speed. The discharge control valve has three main functions:•

They can be used to regulate pumping rates in variable and constant speed pumps and also to prevent overloading in constant speed pumps.

•

They can be used in conjunction with self priming systems to provide a self priming capability in centrifugal pumps.

•

They can be used to reduce the throughput of a pump, and so reduce the Nett Positive Suction Head required.

10.6.2 Self Priming In a self-priming system a discharge control valve performs two duties:•

By restricting the pump throughput, the head is artificially raised to a level above the normal discharge system resistance at that particular throughput.

•

Throughput is reduced to a level equal to, or below, the natural flow of liquid to the pump so that cavitation does not occur, i.e. the flow of liquid to the tank suction strum is closely matched to the pump throughput.

The performance of a centrifugal pump declines if gas is entrained in the liquid being pumped. Manual matching of pump input and output is difficult, and without external aid suction cannot be regained once the strum has been uncovered and air allowed to enter the suction piping. It is for this reason that separate positive displacement pump stripping systems are usually installed. Centrifugal pumps can be made self-priming if air or gas is removed from the liquid being pumped before it enters the pump suction. The discharge valve on the pump performs as important function during this process by matching the discharge rate of the pump to the natural flow of liquid to the pump suction. The sequence of events is: •

Discharge commences, pump and separator fill with oil.

•

Vacuum pump and valve in gas extraction line are shut-off by float switch in pump separator.

•

Discharge valve is fully open, the control system reacting to separator level.

•

Tank level falls to point where separator level begins to fall causing the vacuum pump to start to extract the gases filling the top of the separator preventing cavitation. The extracted gases are vented to a slop tank.

•

As the separator level falls, the control system partly closes the discharge valve on the pump to reduce the output of the pump.

In this way the discharge and stripping operation can continue, the discharge valve being progressively closed, as the vacuum pumps have to work harder to keep the separator full.



: : :


10.7 CAVITATION A pump is said to cavitate when the pressure at the pump suction has fallen to such an extent that bubbles of vapour are formed in the fluid being pumped. In a centrifugal pump bubbles can form with great rapidity at the pump suction and may be carried away to regions of higher pressure within the pump. The bubbles then collapse rapidly and in the process of collapsing creates a hammer effect. This effect, though minute, if repeated frequently, may cause damage to the pump. The residual effects of cavitation, as well as the cavitation itself, can be a problem and include:•

Erosion of metallic surfaces which, if severe, may create flow disturbances.

•

Vibration, which may damage the pump or, more commonly, the instrumentation connected with the pump and installation.

Centrifugal pumps must not be allowed to cavitate.

10.8 PUMP OPERATION PARAMETERS Normally the design of the pumping system makes the need for careful balancing and adjustment of the cargo pump controls during bulk discharge essential to avoid problems. This could be with over heated pumps in the case of high back pressures or overloaded pumps in the case of low back pressures. 10.8.1 Overloading This is a problem with low back pressures from the shore facility and when when the pumps are incorrectly increased in RPM with fully opened discharging lines in an effort to increase the manifold pressure with little or no result, the effect on pump prime mover will be as follows:Output is a function of RPM x Torque, therefore, from even low steam turbine speeds the output from the pump may already be high or maximum, with turbine nozzle pressure (hence torque) at a maximum. Full output at low RPM means that torque can easily increase above the design limits. The high torque results in loads outside the manufacturers design limits which in turn may result in damage to the turbine. The gear trains associated with diesel engine prime movers may also be damaged in a similar fashion if these are similarly overloaded, and indeed bearings and other components in the pumps themselves may be damaged. Particular problems of overloading can occur with the ballast pumps. If the pumps are used to fill double bottoms from empty or empty top wing tanks from full then the pumps can be easily overloaded, causing damage to the prime mover and other components. Careful manipulation of the pump discharge throttle valves is necessary with these pumps. Double bottom tanks are only to be filled from empty by gravity, by passing the pump, and similarly the top wing tanks are to be emptied from full by gravity to pumping level. Overloading of electrically driven ballast pumps can result in the electrical prime mover and other electrical installations burning out.



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To avoid these types of damages the pump must always be operated within their permissible operational envelopes, particularly by keeping the discharge pressure versus RPM within the manufacturers limits by careful use of throttling of the pump discharge valves to create an imposed discharge head. These discharge valves are normally remotely operated from the cargo control room. All centrifugal pumps are to be started with closed or partially open discharge valves to avoid immediate overloading. This is most critical with diesel and electrically driven pumps, rather than the turbine driven pumps where the speed of the pump is gradually increased in a controlled fashion. However, this is good practice for all pumps to ensure that they are always operating within their characteristic envelope. 10.8.2 Underloading Underloading is a problem with high back pressures from the shore facility. Underloading results in overheating of pump casings and damage to pump components due to energy developed by the pump mover being converted into heat rather than in pumping the cargo ashore. Pump balance is at its most critical when high back pressure from the shore facility is experienced. 10.8.3 Pump Characteristic Diagram These are diagrams showing pump operational parameters, and contain information, including volumetric output against RPM, discharge head, power, steam consumption, etc. Each type of pump will have its own characteristic diagram and all operators must be aware of, and follow, the limitations of these parameters. The diagrams must be clearly displayed at the pump operating position. 10.8.4 Balancing/Discharging Using More Than One Pump When more than one pump is discharging to a common shore line it is essential that the pumps are correctly balanced so that they meet the parameters of their operating envelopes to avoid overloading or underloading. Balancing of the pumps is best achieved by monitoring of the pump discharge pressure gauges, as the pumps are usually not fitted with remote indicators in the cargo control room to show whether the pump non return valves are open and consequently each pump is actually pumping cargo. The RPM in itself cannot be relied upon to balance the pumps, as different pumps may be operating with different suction pressures. It is therefore important that the pump discharge pressure indicators, and transmitters are working correctly and are properly calibrated at all times. During the balance process the pumps are to be monitored locally to ensure that heating of casings is not occurring so that prompt corrective action can be taken to prevent a pump shutdown by one of the safety devices. If this balancing is correctly achieved it can be assumed that each pump will be delivering its own proportion of the total volume of cargo being delivered ashore, and therefore a check can be made to ensure that the pumps are operating within their characteristic envelopes. If this is not the case then the pump discharge throttle valves are to be adjusted until the discharge pressure on the pump is correctly within design limits.



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10.9 SUBMERSIBLE PUMP PURGING ROUTINES Submersible pumps are purged, using inert gas (ship’s IG or nitrogen) or air, as a means of checking for seal condition and tightness. The pumps must be purged before and after every loading/discharging operation and the appropriate record form completed. Action is to be taken, at the first opportunity, if the pump cofferdam becomes blocked or if seal leakages are detected.

10.10 EDUCTORS Eductors may be used for ballast stripping purposes. To strip efficiently, an eductor used for tank cleaning operations should have a capacity of about twice the rate of liquid being introduced to the tanks. •

Eductors are always to be operated at or near their design driving pressure as, in general, lower driving pressures will considerably reduce eductor efficiency. Higher back pressures in the system than the eductor was designed for can also reduce suction capacity.

•

The eductor drive liquid must always be flowing before the suction valve is opened to prevent back flow of the driving liquid to the tank suction.

•

When shutting down an eductor the suction valve is to remain open until the eductor is stopped to prevent the eductor drawing a vacuum on the suction line.

•

If, during use, the eductor driving pressure falls below the required operating pressure, the eductor suction valve is to be closed to prevent backflow of the driving liquid. The tank suction must not be used to prevent backflow as the suction pipework is not designed for such high operating pressures.

CHEMICAL TANKER MANUAL SECTION 11 – TANK CLEANING


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11. TANK CLEANING 11.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section. Location

Publication MARPOL 73/78 Ship’s “Procedure and Arrangements Manual” (Approved by Class) The ICS Tanker Safety Guide (Chemicals) International Safety Guide for Oil Tankers and Terminals (ISGOTT) Tank Cleaning Guide (Dr.Verwey)

Master Master Chief Officer Chief Officer Chief Officer

11.2 COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Company Form No TNK 10

Title Tank Cleaning Record

11.3 TANK CLEANING INSTRUCTIONS Tank cleaning instructions for vessels on time charter will come from the Charterers. Tank cleaning instruction for vessels on voyage charter will normally be taken from the industry guides provided on board and as listed in the Publications Index. Any specific tank cleaning instructions contained in a Charter Party must be strictly adhered to unless those instructions are likely to pose a threat to the ship’s safety or the environment. In this case the Company must be consulted immediately. Various tank cleaning methods are described in general and in particular in the Dr Vervey Tank Cleaning Guide Notwithstanding any of the above, if in doubt, the Management Office is to be consulted.

11.4 TANKCLEANING 11.4.1 General Tank cleaning is required to make a tank ready for the loading of the next cargo. How much cleaning is required depends on the nature of the previous and the next cargo as well as external factors such as: air temperature, seawater temperature, weather conditions etc. and the efficiency of the vessel’s cleaning equipment. Tank cleaning on a chemical tanker varies widely depending on the cargo to be cleaned and the cargo to be loaded.



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In the absence of specific loading instructions tanks should be cleaned to Water White standard (WW-standard) as a minimum in order to have the maximum flexibility for the stowage of the next cargo(es). The risks involved in tank washing when dealing with dangerous chemicals are much greater than those involved in loading and discharging operations. There is a constant risk of direct contact with dangerous substances in gaseous, liquid or solid form, released during the process. The crew are to be thoroughly briefed on possible safety hazards and the safety precautions to be taken during the cleaning. A responsible officer must always be in charge of cleaning operations, and written cleaning instructions must be available to all personnel involved. It must also be recognised that certain cargoes may react with the cleaning media and produce large amounts of toxic or flammable vapours or react in a way that make equipment, like pumps inoperable. Tank cleaning/gas freeing on a chemical tanker is recognised to be the most dangerous operation conducted on board and rigorous precautions must be observed throughout these operations. One must expect that toxic, corrosive and flammable vapours are released onto and around the cargo deck areas. During tank cleaning the cargo tank atmosphere must be regularly monitored especially when the tank previously contained a flammable product. It is therefore of greatest importance that personnel involved are fully aware of these dangers and take the necessary precautions. 11.4.2 Safety requirements Tank cleaning is a hazardous operation which requires an increased level of safety awareness. Additional safety precautions must include, but not be limited to the following:-

•

Smoking regulations must be in force as for a load or discharge port.

•

All doors and windows kept closed.

•

Air conditioning must be on full recirculation.

•

No unauthorised personnel allowed on deck.

•

Other safety requirements as per the current edition of the ISGOTT guide / MSDS. •

-Characteristics of the product must be available.

•

-Written instructions must be issued

•

-Equipment to be used must be checked and be in order

•

All portable hoses to be used with portable tank cleaning machines must be tested in a dry condition for electrical continuity prior to the operation and must not be used if the resistance exceeds 6 ohms per metre length.

•

-Personal protective equipment must be ready and used when necessary



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•

-Fire fighting equipment must be ready for use

•

-If in port or alongside berth permission from local authorities or terminal must be obtained

11.4.3 Water white standard Definition •

No trace of cargoes in tank and its associated systems Cargo line P/V line Stripping line Vapour return line

•

No odour

•

Chlorides < 10 ppm

•

No suspended matter (floaters or other visual particles).

•

No discoloration from last cargoes or due to tank cleaning.

•

Heating coils clean and bright

•

Tank hatch & tank cleaning hatch packing clean and free from odour.

11.5 PREPARATION FOR TANKWASHING 11.5.1 Cleaning program and plan Planning of the tank washing program must begin before the port of discharge is reached. A cargo tank cleaning program has to be prepared and posted. The most important sources of information for planning besides the experience of ship’s management are: •

P&A Manual

•

Product information and instructions from the manufacturer

•

The ICS Tanker Safety Guide (Chemicals)

•

Cleaning reports from earlier experience

•

This Manual

•

Dr Vervey Tank Cleaning Guide



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Prior to commencing any tank cleaning a written plan must be produced by the Chief Officer, in consultation with the Chief Engineer, and approved by the Master. The plan is to include, but not be limited to the following:•

Full details and method used for the tanks to be cleaned.

•

Can water be used, whether to use hot or cold water first, what chemicals can/should be used. Always clean to water white standard.

•

The positioning of machines and the proposed time schedule.

•

Details of pump operation.

•

Intended ballast changes and time schedule in relation to the cleaning program.

•

Stability during the cleaning programme - before, during and after any ballast changes.

•

Line washing/cleaning plan.

•

Slop discharge plan.

•

Watches and duties of personnel involved in the operation.

•

Instructions to cleaning personnel.

11.5.2 Tankwashing briefing All responsible personnel are to take part in the tankwashing briefing. Additional crewmembers are to be involved as required. The briefing should include the following: •

Safety measures and protective clothing required during the cleaning operations

•

Safety information regarding tankcleaning risks

•

Planned schedule and technical course of action

•

Anything other that is relevant

Safety measures are to be agreed upon for those working directly in the tanks as well as other crewmembers. These safety measures should be posted in conspicuous places. It is especially important that the external doors remain closed, ventilation is switched to recirculation, and that smoking prohibition is strictly observed. No welding or any other hot work causing sparks is to be allowed. All tankwashing operations are to be carried out in accordance with MARPOL regulations. Trim and list of the ship are important during tankwashing to make sure that the washwater flows unhindered to the pump wells. The MARPOL underwater discharge line has to be used when pumping residual material from noxious liquids overboard.



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11.6 SPECIAL CLEANING PRECAUTIONS 11.6.1 Cleaning of flammable products When cleaning flammable products the atmosphere of the relevant tanks and deck areas have to be frequently monitored due to the risk of fire and explosion. The results must be recorded. According to the results the Chief-officer and Master must consider suitable precautions in order to avoid the risk of explosion. (e.g. caused by static electricity). (See also sections 3 + 9). 11.6.2 Cleaning of toxic products When cleaning toxic products the atmosphere has to be monitored frequently for presence of toxic gases. The result must be recorded and the Master should consider whether suitable precautions have to be observed. If necessary the vessel’s course should be altered. 11.6.3 Tankcleaning Slops Prewash slops should be discharged ashore. Other slops can be stored in a designated tank to be disposed of later according to Marpol regulations. When pumping different slop i.e. from different products into one sloptank the compatibility of the noxious products should be taken into consideration. If the products are not compatible an additional sloptank must be used. 11.6.4 Cleaning coated tanks Guidelines issued by the coating manufacturer must be consulted prior to any cleaning as the coating may require time to cure after discharge and prior to adding any water to the tank. When tank cleaning coated tanks the temperature of the washing water must not exceed the paint manufacturers guideines as damage to the coatings may result.

CHEMICAL TANKER MANUAL SECTION 12 – BALLAST OPERATIONS


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12. BALLAST OPERATIONS 12.1 REFERENCE PUBLICATIONS Publication MARPOL 73/78 IMO Resolution A.774(18) – “Guidelines for Preventing the Introduction of Unwanted Aquatic Organisms and Pathogens from Ship’s Ballast Water and Sediment Discharged” Ship’s “Dedicated C.B.T. Operations Manual” Approved by Class Ship’s “Procedure and Arrangements manual” (Approved by Class) International Safety Guide for Oil Tankers and Terminals (ISGOTT) Clean Seas Guide for Oil Tankers Guide to Port Entry

Location Master Master Master Master Chief Officer Chief Officer Master

12.2 COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Company Form No

Title

MAR 08 SAF 11 SAF 15

Cargo Loading/Discharge Plan Enclosed Space Entry Permit Ballast Water Management Plan and Log

12.3 GENERAL When the ship is not carrying cargo or is lightly loaded, sufficient ballast must be carried to ensure that the ship’s stress, stability, draft, trim and propeller immersion is within permissible limits to guarantee the safe handling of the vessel in the prevailing or expected conditions. In meeting these parameters the vessel must comply, at least, with the requirements of the IMO, Class (especially appendix to Class Certificate) and Port State Authorities. In 1993 IMO has adopted Resolution A.774(18) “Guidelines for Preventing the Introduction of Unwanted Aquatic Organisms and Pathogens from Ships’ Ballast Water and Sediment Discharges”. The procedures that the Company view as the most practical to comply with this IMO Resolution are described in this section, and Masters are to ensure compliance with them. Ballast operations must always be carried out within the capabilities of the vessel and its systems and if the vessel is unable to follow any of the procedures described below the Company is to be advised.

12.4 DESIGNATED OFFICER The Chief Officer is designated to carry out these procedures and maintain all records as required.



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The Master is to ensure the Chief Officer is familiar with the requirements of this section including IMO Guidelines. The Master must also ensure that all the crew members are given the instruction and are aware of the need for ballast water control procedures and the procedures being adopted on board.

12.5 PLANNING OF THE BALLAST OPERATIONS Ballast operations are always to be planned in advance by the Chief Officer and entered on the Cargo Loading and Discharge Plan Form MAR 08. The plan is to be approved by the Master prior to commencing the operation. In port, the plan must be discussed and agreed with the terminal personnel. Each vessel must produce a standard plan for a complete change of ballast.

12.6 RECORDS AND REPORTING When taking on ballast waters, the date and time of commencement and completion of the ballast operation, ship’s position, salinity (specific gravity) and amount of ballast water taken onboard must be recorded in the ship’s Deck Log Book. A report in the format shown in the appendix to IMO Guidelines must be completed by the Master and made available to the Port State Authority on request. Analysis certificates, ballast reports and shore receipts must always be kept on board in a separate file. On tankers, any ballasting or deballasting of cargo tanks are to be recorded, and shore receipts kept in the Oil Record Book Part II or Cargo Record Book (NLS) as required by Annex I and II of MARPOL 73/78. When the Port State Authority water ballast control requirements (e.g. exchange of ballast at sea) cannot be met during the voyage due to weather condition, operational impracticability, etc, the Master must report this fact to the Company and the prospective Port State Authority prior to entering its national waters (economical zone), so that appropriate alternative action can be arranged.

12.7 CONTROLS APPLIED BY PORT STATE AUTHORITIES The Master is to check in advance with the local agent, and the latest Port Guide , for any information on ballast water sediment discharge procedures, being applied by the State Authorities at an expected port of call. These procedures may include, but are not limited, the following control actions: •

The non-release of ballast water;

•

Ballast water exchange and sediment removal at sea or in acceptable areas;

•

Ballast water management practices aimed at minimising the uptake of contaminated water in ballasting and deballasting operations;

•

Discharge of ballast water into shore-facilities.



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Failure to comply with national requirements may lead to unnecessary delays for the ship. In some cases penalties may be applied by Ports State Authorities. The vessel may be required to proceed to an approved location to carry out the necessary exchange, seal the ballast tanks against discharge in the Port State’s waters, pump the ballast water to shore reception facilities, or prove, by laboratory analysis, that the ballast water is acceptable.

12.8 LOADING OF BALLAST WATER When loading ballast every effort is to be made to ensure only clean ballast is being taken onboard and the intake of sediment is minimised. Where practicable vessels are to avoid taking on ballast water in shallow water areas or in the vicinity of dredging operations. Vessels must not ballast if at all practicable in areas where there is a known outbreak of water communicable diseases or where phytoplankton blooms are occurring. It is recognised however, that when vessels trade to river or estuary ports, intake of some silts and sediments is unavoidable. In such situations the amount of silt taken on board can often be substantially reduced by planning to ballast on the flood tide when the suspended silt levels are normally lower. Vessels taking on ballast in river or estuary waters or any other areas where the purity of the water is in doubt, including areas of probable contamination from chemicals, disease, pathogens etc. must follow the control procedures as described in 12.10. When segregated ballast has been loaded in stilted or otherwise polluted water, the ballast is to be changed as soon as possible after leaving that port. It is also essential that this is carried out to prevent the build up of mud in ballast tanks which may reduce the vessels cargo lifting capacity. Whenever possible the initial filling of the ballast tanks should be running in from the sea by gravity in preference to pumping in. In general, segregated ballast tanks are to be filled to 100% capacity but not be overflowed. 12.8.1

Ballasting of Cargo Tanks On vessels classed as SBT, ballast must only be loaded into segregated ballast tanks. Where the Master considers that additional ballast is necessary as permitted by MARPOL 73/78, then the regulatory requirements are to be complied with. If it is necessary to mount special spool pieces in order to carry out ballasting of heavy weather cargo tanks, the spools are to be removed as soon as such ballasting is completed.

12.9 BALLAST WATER EXCHANGE AND SEDIMENT REMOVAL The most realistic and practical method for the control of transportation of marine organisms and to control sediments, is to exchange ballast water in deep ocean or open sea areas. This will limit the probability that fresh water or coastal species will be transferred in the ballast water. The responsibility for deciding on such action rests with the Master. The Master must contact the Port State Authority of his next port via the agents and determine if special control actions are required.



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The exchange is to be conducted in water depths greater than 2000 metres, or in those cases where this is not possible, exchange of ballast water is to be made well clear of coastal and estuary influences. Draining of each tank is to be done until pump suction is lost. This will minimise the likelihood of residual organism survival. The tank is then to be flushed over the bottoms by refilling (if possible – by gravity) to approx. 0.5 metre depth, twice, each time followed by complete draining until pump suction is lost. The tank is then to be refilled. The effectiveness of this flushing can be increased if the vessel is on a course that causes the vessel to roll slightly, however, the vessel must not deviate greater than 15o from the intended voyage course during the time of flushing. When heavy sedimentation is observed after visual inspection, then manual sediment removal may be undertaken. Tanks shall be inspected visually for sediment build up at least once every three months wherever practical, and sediment build up recorded on the tank condition report which is to be forwarded to the Company. 12.9.1

Flow Through Exchanges When a vessel cannot conduct a complete ballast change, a “flow through” (through ballast tank vents) exchange of ballast water may be an acceptable alternative for some tanks, however, it has little effect on sediment control. Due to the risk of building up the pressure in ballast tanks, and the possibility of damage to vent heads, screens, etc. this procedure would require Administration (Classification) approval and must not be attempted without prior special considerations and authority of the Company. Modification of tank venting arrangements may be necessary to avoid damage to the vent heads and screens.

12.9.2

Discharge of Ballast Water in Cargo Tanks Dirty ballast is to be processed and discharged in accordance with the current editions of “Clean Seas for Oil Tankers” and the MARPOL 73/78 Annex I and II regulations. The discharge of ballast from cargo tanks whether dirty or clean is to be carried out with the Oil Discharge Monitoring Equipment (O.D.M.E.) in operation. During the discharge of dirty ballast overboard the performance of the O.D.M.E. is to be checked by frequent visual inspections to guard against accidental pollution. When the overboard discharge is stopped by the monitoring equipment, the remaining oily water is to be retained and transferred to the primary slop tank for settling. Any line flushing necessary is to be made into the slop tanks. After settling of the slop tanks the free water is to be decanted to sea via the O.D.M.E and on completion any lines used are to be stripped into the primary slop tanks.

12.10 DISCHARGE OF BALLAST WATER No ballast is to be discharged in the continental shelf, coastal or port waters where ballast water and sediment control measures are being applied by State Authorities, unless ballast water and sediment control procedures have been followed, or acceptable alternatives have been adopted. The effectiveness of the vessels procedures may be verified by Port State Authorities taking samples of ballast water and/or sediments from the vessel, to test for the continued survival of unwanted aquatic organisms and pathogens. Such samples may also be taken from suction wells, chain



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lockers and other areas where sediment may accumulate. In certain cases discharge of ballast will not be permitted until analysis of such samples is completed. The Master is to ensure that relevant written authorisation is obtained from the Port Authority prior to discharging any ballast to coastal waters of any country that exercises ballast control measures. Shortly after commencement and during discharge of any ballast overboard the surface of the sea is to be checked frequently to guard against accidental pollution. Whenever possible, initial deballasting of SBT is to be by gravity in preference to pumping out. 12.10.1

Discharge of Ballast Water to Shore Reception Facilities

Some terminals are already adopting this practice and have done so for many years, as local conditions do not allow any discharge of ballast whatsoever. The Master is to check with the terminal of any requirements for shore based discharge of ballast through voyage orders, agents instructions, “Guide to Port Entry”, etc. If there is any doubt the Company must be referred to for advice, well before arrival. Generally SBT vessels are not provided with a direct means to discharge ballast ashore. In this case it will be necessary to either: •

Fit a spool piece between the cargo and ballast suction piping, and to use a cargo pump for discharging of the ballast to the manifold. For this purpose the following precautions shall be taken:

•

All cargo system valves that isolate the cargo being loaded, from the ballast being discharged shall be pressure tested and verified tight.

•

Two valve separation between cargo and ballast is to be maintained. In most cases this will require careful planning of the loading and deballasting operation to ensure, the requirement is met.

•

The spool piece is to be removed and pipes blanked immediately on completion of the deballasting operation.

•

Load ballast in cargo tanks and discharge all ballast tank water in deep ocean areas prior to arrival, with particular reference to Company approval, if tanks not normally designated for ballast water are to be used. Two valve separation is to be maintained between the tanks being loaded and deballasted. These valves are to be tested and verified prior to the operation.

12.11 SAMPLE ANALYSIS CERTIFICATE Vessels may avoid ballast changing in some circumstances by having their ballast water or harbour source samples analysed by a laboratory at the departure port. Where the analysis shows the ballast or sediment to be free from unwanted aquatic organisms or pathogens an analysis certificate is to be provided by the Master to the Port State of arrival. This must be carried out by fax several days prior to arrival in case the analysis is rejected, so that the ballast change procedures can be applied prior to arrival.



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12.12 MANUAL REMOVAL OF SOLID ELEMENTS Care is to be taken when manually removing sediments while the ship is in port or in continental shelf waters, to ensure sediments are not discharged into these waters. Sediments must be disposed of ashore and processed according to the local requirements. A log book entry is to be made and receipts obtained. This part applies to solid sediment discharges, and does not affect sediments that can be removed from the chain locker or wells by hand hosing.

12.13 BALLAST OPERATION PRECAUTIONS 12.13.1

Personnel Safety

If tank entry is required to affect the taking of samples, carrying out a ballast tank inspection, or for manually removing solid sediments, then all the safety precautions and “Entry into Enclosed Space” Entry Permit Form SAF 11 Requirements must be complied with. 12.13.2

Ship’s Safety

When planning and carrying out operations with ballast waters, the following factors must be taken into account: •

Shear Force and Bending Moment

•

Stability and Free Surface Effect

•

Slack Tanks

•

Torsion Loads

•

Draft and Trim of the Vessel

The Ship’s course and speed is to be properly set depending on the prevailing weather conditions. Sufficient personnel must be available to allow safe monitoring of the operation. 12.13.3

Ballast Tank’s Venting System

If it of paramount importance that all segregated and permanent ballast tank vents are properly set up and in good condition prior to any ballast operation. All vent closures that are capable of manual operation must be in the open position. The original design venting capability must be available at all times. The vents are to be further checked soon after starting the operation to confirm that the tanks are venting freely. Improperly set ballast vents can result in severe structural damage to the vessel. Vent screens are to be kept free from paint as this can seriously reduce their volumetric capacity.



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Great care is to be taken in conditions where icing is occurring. In certain circumstances screens on ballast tank vents can become blocked by icing. During ballast operations in such conditions, the responsible officer is to ensure that all precautions are adopted to ensure the free venting of ballast tanks, and that regular checks are made to ensure continuous free venting throughout the operation. 12.13.4

Pumping Limitation

During pumping of ballast care must be taken not to operate the pumps above the maximum safe rate. In this respect the ballast pump capacity must be borne in mind with respect to the maximum ballasting rate of any given tank or sets of tanks. When ballasting at sea in heavy weather, there is a significant risk to personnel on deck and it may be more prudent to “run in” the ballast by gravity to a number of tanks.

12.14 CATHODIC PROTECTION Uncoated clean ballast tanks have a sacrificial zinc anode system fitted to protect the entire tank structure. Uncoated dirty ballast tanks have a sacrificial zinc anode system fitted to protect the bottom shell plating only to guard against pitting. CBT product carriers with coated tanks have anodes fitted in designated ballast tanks, sufficient only to protect the tank coatings and the underlying steel in the event of a coating breakdown. Care must be taken to avoid over protection in the tanks as this can lead to coating breakdown. It is important that ballast is loaded into protected tanks only, and any deviation from this requirement in order to affect ballast control procedures must receive approval from the Company. If loading ballast into tanks fitted with cathodic protection in a freshwater river or estuary it is also important to change the ballast at sea as soon as practical in order to achieve the full effect of the cathodic protection system.

12.15 BALLASTING CARGO TANKS – SAFETY CONSIDERATIONS Modern chemical tankers are in compliance with MARPOL ‘s segregated ballast requirements and infrequently uses cargo tanks for ballast. This section will only deal with ballast in cargo tanks. Ballasting cargo tanks may put extra stresses on the hull, or create other safety hazards if the tanks contain cargo residues. •

A responsible officer must be in charge of ballasting a cargo tank

•

Determine if the tank is clean or contains cargo residues that may react in a hazardous manner with the ballast water

•

Ballasting may cause flammable, toxic or corrosive vapours to be released onto, or around, the cargo deck area

•

Never overflow a ballast cargo tank



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•

A cargo tank containing dirty ballast should be “tagged” and marked as such

•

Upon completion of ballasting all openings to be closed down and secured


Discharging of ballast from a cargo tank must only take place according to the MARPOL convention and/or local requirements. If for any reason a stainless cargo tank has to be ballasted with seawater the Master should consult the Management Office as seawater may cause severe pittings in the stainless steel. In any case after a stainless steel cargo tank has contained seawater the tank and its associated piping system should be thoroughly rinsed with fresh water.

CHEMICAL TANKER MANUAL SECTION 13 - EQUIPMENT


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13. EQUIPMENT 13.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section. Publication

Location

Equipment Manufacturers Instruction Manuals International Safety Guide for Oil Tankers and Terminals (ISGOTT) CFR 33 parts 125 to 199

Chief Officer Chief Officer Master

13.2 LOADING/STRESS COMPUTER This instrument is provided to supplement the stability booklet for the vessel. It allows the Officer responsible, to carry out the various complex calculations required to ensure that the ship is not overstressed or damaged during the carriage of the nominated cargoes. It will also permit the assessment of damage stability. It must be remembered that a loading computer, as with navigation aids, is only an aid to the operator. It relies on human input of data, and more importantly the human interpretation of the output data. If the input data is incorrect, the output data will also be incorrect. Used correctly it will ensure the safe operation of the ship for all conditions of loading, discharging, ballasting and at all stages of the voyage. It is a requirement that where such equipment is provided to a ship, test conditions must also be supplied for use in verifying the accuracy of the equipment. It is Company policy that test conditions must be run as soon as possible after a change of Chief Officer and at least every three months and in any case prior to the vessel proceeding to drydock. Where the running of these reveal significant errors the Company is to be advised immediately with a request for attention.

13.3 P/V VALVES Pressure/Vacuum valves are designed to provide protection of all cargo tanks and provide for the flow of small volumes of tank atmosphere resulting from temperature variations in the cargo tank(s) and should operate in advance of the pressure/vacuum breaker. P/V valves are to be clearly marked with their high pressure and vacuum opening pressures. Hi-Jet type high velocity pressure/vacuum valves are designed to provide protection to individual tanks and are capable of allowing high volumes of tank atmosphere to pass, as would be the case during loading. They are also designed to throw the vented gases clear of the deck area. They are not designed to be operated in the “jacked-open” position and should only be used in this way when there is no alternative. The correct maintenance of these valves is essential to the safe operation of the vessel. To ensure this, these valves are to be inspected regularly and thoroughly overhauled and cleaned at least every six months, or more frequently if specified by the manufacturers instructions.



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13.4 FLAME ARRESTOR GAUZES Flame gauzes/screens on P/V valves, Hi-Jet type valves, vapour lines, mast risers, purge pipes, p/v breakers and on ullage ports are to be inspected every three months and replaced as necessary. Flame screens on ballast tank and bunker tank vents must be inspected every six months and replaced, as necessary.

13.5 P/V BREAKER Every inert gas system is required to be fitted with one or more pressure/vacuum breakers or other approved devices. These are designed to protect the cargo tanks against excessive pressure or vacuum and must therefore be kept in perfect working order by regular maintenance in accordance with the manufacturer’s instructions. When these are liquid filled it is important to ensure that the correct fluid is used and the correct level maintained for the density of the liquid used. The level can normally only be checked when there is no pressure in the inert gas deck main. Evaporation, condensation and possible ingress or sea water must be taken into consideration when checking the liquid condition, density and level. In heavy weather, the pressure surge caused by the motion of the liquid in the cargo tanks may cause the liquid in the pressure/vacuum breaker to be blown out. When cold weather conditions are expected, liquid filled breakers must be checked to ensure that the liquid is suitable for low temperature use, and if necessary anti-freeze is to be added. The P/V breaker(s) are to be clearly marked with their high pressure and vacuum opening pressures and also with the type and volumetric concentration of antifreeze (if water filled type), and minimum operating temperature.

13.6 DECK SEAL & NON RETURN CHECK VALVES On vessels fitted with an inert gas system it is a requirement to maintain a positive seal between the cargo tanks and the inert gas generation plant this is usually accomplished by the use of a nonreturn valve and a Deck Water Seal. The water seal and non-return valve ensure that the cargo tank atmosphere cannot leak back to the engine room or inert gas generator. In vessels fitted with a Venturi type “Dry” deck water seal, particular care must be taken with inspections of the Venturi non return valves and/or orifice plates, as applicable, to ensure that there is no corrosion or damage which would allow excessive carry over of water into the inert gas piping system and cargo tanks. Filters in the system must be removed regularly for inspection and repair if necessary. When vessels are trading in cold weather areas it is essential that deck seal heating systems are checked as being operational. During carriage of flammable cargoes, including when there is a presence of flammable slops onboard, the deck seal pump shall be kept operational on a continuous basis and all alarm systems relating to the pump pressure, or level of water in deck seal, shall be kept in full operation. Deck seals and non-return valves shall be opened up at periods not exceeding 12 months for inspection of all internal parts, venturies etc.



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13.7 TANK GAUGING The components of all cargo and ballast tank level gauging equipment are to be operationally tested prior to every cargo operation and inspected/cleaned as required, according to the maker’s instructions at least every six months.

13.8 PUMPROOM BILGE LEVEL ALARMS Pumproom bilge alarms are to be tested weekly, and prior to every cargo operation.

13.9 PUMP SUCTION STRAINERS The continued efficient operation of cargo pumps requires that any pump suction strainers fitted are kept clean as follows:•

Main cargo pump suction strainers are to be opened up for inspection and cleaning at least once every six months and may also require inspection/cleaning between grades.

•

Cargo stripping pump suction strainers are to be opened up for inspection and cleaning at least once per ballast voyage after tank cleaning has been completed

•

Ballast pump suction strainers are to be opened up for inspection and cleaning at least once every year.

13.10 PUMP SAFETY DEVICES Cargo and ballast pump safety devices are to be tested at least once per loaded voyage, just prior to the first discharge port, or monthly on voyages of short duration before commencement of discharge. On satisfactory completion of the tests an appropriate log entry is to be made.

13.11 TANK CLEANING EQUIPMENT Tank cleaning machines, when not being used regularly, are to be checked in accordance with the manufacturers instructions, at least every three months. Tank cleaning hoses are to be checked for electrical continuity before each operation, should there be any doubt about their condition deteriorating since last routine testing (otherwise every three months).

13.12 GAS DETECTION EQUIPMENT Each vessel is supplied with portable gas detection equipment according to the list contained in the Safety and Environmental Manual. Each piece of equipment is to be checked before each use. A calibration check is to be carried out on all portable equipment every two months. Fixed gas detection equipment is to be checked weekly or before each load/discharge port on shorter voyages. A calibration check is to be carried out every two months.



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13.13 PRESSURE GAUGES All manifold and other pressure instrumentation within the cargo system is to be checked annually for calibration. Vessels are supplied with one test gauge (certified) for this purpose and all other gauges are to be checked against the calibrated gauge. Gauges are to be checked within +/- 10% of the certified gauge and a certificate issued by the Chief Engineer. An entry is also to be made in the deck log book. The certified gauge is to be used only for calibration purposes. Any gauges which cannot be calibrated to within +/- 10% of the certified gauge are to be replaced.

13.14 TANK HIGH LEVEL AND OVERFILL ALARMS 13.14.1

High Level Alarms

Alarms shall be properly set and tested prior to each cargo operation. For this purpose they shall not be set to higher level than 95%. 13.14.2

Tank Overfill Alarms

All tank overfill alarms shall be tested by manual lifting of the float, or other local test device, prior to each cargo operation, according to makers manual. Tank overfill alarms are to be switched on and operational during all cargo operations. Log entries are to be made confirming the above, with any defects being advised to the office immediately. The audio and visual alarm positions on deck must be clearly identified with a stencil of 50mm height in black letters on white – “TANK OVERFILL ALARM”. If each tank has a different alarm the tank must also be identified. Both a high level alarm and an overflow alarm may be fitted as a requirement of the IBC/BCH Code. Both systems must be totally independent of one another and give visual and audible alarms.

13.15 TANK RADAR SYSTEMS Occasions have occurred where tank radar ullage indications have failed to indicate correctly, without warning. Usually after cleaning of the transmitter antenna, as per the manufacturer’s instructions, the correct indication is restored. All vessels fitted with tank radar ullage systems are to carry out regular cleaning of radar antennas as cargo carriage allows. A notice is to be displayed in cargo control room to that effect.

13.16 OIL DISCHARGE MONITORING AND CONTROL EQUIPMENT Vessels fitted with equipment for monitoring the discharge of effluent from slop tanks must ensure that this equipment is operational before any discharge is made. The operation of this equipment



: : :


must be in accordance with the approved “Oil Discharge Monitoring and Control Systems Operation Manual”. A calibration check according to the manufacturers manual is to be carried out at intervals not exceeding one month. Printed records from the monitoring equipment must be retained on board for inspection by surveyors.

13.17 PORTABLE HERMETIC GAUGING AND SAMPLING EQUIPMENT Every vessel must be provided with a minimum of three units capable of closed measuring of ullages and temperatures One unit shall also be capable of determining interface readings. Prior to each use, for determining cargo quantity the equipment shall be checked fully operational and calibration of temperature sensors checked against a certificated reference thermometer. Each instrument shall be calibrated by an independent organisation once per annum. Earthing requirements of the instrument must always be complied with, as per the manufacturers instructions. Every vessel shall also be provided with a closed sampling device.

13.18 TRANSFER EQUIPMENT TEST AND INSPECTIONS Requirements of this section apply on pipes, hoses, valves, gauges and other associated equipment of cargo, bunker, ballast and vapour emission control systems. Frequency and procedures of tests and inspections of transfer systems and other equipment, unless otherwise specified by the Company, Charterers or Port Authorities, must be in compliance with the requirements of 33 CFR 156.170. On satisfactory completion of the tests and inspections an appropriate Deck Log Book entry is to be made.

13.19 VALVES Valve integrity is essential in maintaining a fully operational and reliable cargo pipeline system and hence, the operation of a tanker. All vessels must carry out a valve function test every 6 months to check the following: •

That all valves operate throughout their full range.

•

That all valves close fully.

New vessels must, in addition, carry out this test prior to arrival at the first load port. To ensure that valves are not leaking all valves are to be pressure tested whenever it is practicable every six months. This will require the Chief Officer to draw up a comprehensive test programme, which allows the checking of all valves in the system.


13.19.1


: : :


Sea Suction and Overboard Valves

Prior to every loading and discharge port the pipes between the double sea suction and overboard valves in the cargo system are to be drained of water and air tested. Air pressure up to maximum. 3kg will be steady if there is no leakage of the valves. Tests are to be entered in the ‘Deck Log Book’. Any leakages detected are to be immediately advised to the Company. This test is not required if physical blanks are used in the line. After completion of testing the air pressure is to be reduced to zero. 13.19.2

Pipelines

As with the valves, it is essential that all cargo, COW, ballast and bunker pipework remains in good condition. To ensure this, all cargo, ballast and bunker pipework is to be annually pressure tested, and must not leak under static liquid pressure at least 1.5 times the maximum allowable working pressure. On satisfactory completion of the test a suitable Deck Log entry is to be made. The entry required is as follows: “Deck cargo lines tested to … (insert test pressure)”. The pressure used and the date is to be stencilled on each line adjacent to the manifold on both sides of the vessel.

13.20

FLEXIBLE HOSES Cargo transfer hoses are to be tested annually and must not burst, bulge, leak or abnormally distort under static liquid pressure at least 1.5 times the maximum allowable working pressure. This is in addition to electrical continuity tests and inspection for general condition and cleanliness.

13.21

CALIBRATION

13.21.1

General

This procedure describes the monitoring of test devices used for activities that influence the quality of the services the vessel provides and are not subject to external, regular inspections on account of national and international regulations. It must be ensured that these test devices are subjected to a planned monitoring system and are calibrated or adjusted at determined intervals to keep their measuring deviations within the tolerances. Monitoring of measuring and test devices comprises the following tasks: •

Recording and registering of the measuring devices concerned

•

Identification of measuring devices using test stickers, serial numbers, engraved identification numbers or precise description of place of installation

•

Setting up and constant updating of a monitoring schedule covering all devices to be calibrated and scheduled calibration at least once in 24 months or in line with manufacturers recommendations

•

Calibration of the devices concerned where achievable on board.


•

13.21.2


: : :


Documentation of calibrations made and withdrawing defective measuring and test devices from service.

Calibration method

All measuring and test devices used must be calibrated to standards / measurement standards as per monitoring schedule. The standards must have a known relation to national or international standards and must be mutually convertible with them. The measurement standards used are subject to re-calibration. 13.21.3

Documentation

The measuring and test devices to be monitored are to be documented according to your company’s instructions. If calibration tasks are to be carried out by other companies, the name and type of such a firm must also be entered. 13.21.4

Designation of measuring and testing devices

Following measuring and testing devices are covered by this procedure: •

Thermometer used for cargo operations monitoring

•

Manometers used for cargo operations monitoring

•

Tank level gauging systems

•

Explosimeter

•

Oxymeter

•

Other cargo monitoring equipment.

Calibration has to be carried out in accordance with the manufacturer’s and/or the Company’s instructions. 13.21.5

Defective measuring and test devices

Test devices that are defective or do not lie within the tolerance limits, or cannot be re-calibrated, must be withdrawn from service and replaced immediately with new devices.

CHEMICAL TANKER MANUAL SECTION 14 – DOCUMENTATION AND CARGO CALCULATION


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VMS/CHM/01 01 1 of 10

14. DOCUMENTATION AND CARGO CALCULATION 14.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section. Location

Publication API/ASTM-IP Petroleum Measurement Tables Vols. I, II, VII, VIII & XI/XII Ship’s Ullage and/or sounding tables. Ship’s “Trim and Stability Data/Manual” (Approved by Class)

Chief Officer Chief Officer Master

14.2 COMPANY FORMS The following Company Forms are to be used in conjunction with this section: Company Form No SAF 20 MAR 01 MAR 02 MAR 03 MAR 05 MAR 06 TNK 01 TNK 04 TNK TNK TNK TNK TNK TNK TNK TNK

06 07 08 09 10 11 12 15

Title Deck Log Book Sea Passage Report Port Log Notice of Readiness Deadfreight Statement Protest of Difference Between Ship and Shore Figures Pre arrival and Commencement – Cargo Operations Checklist Prior to Use of Vapour Emission Control System Checklist Ullage Report Pumping Record Cargo Heating Report Inert Gas Log Tank Cleaning Record ROB Report Dry receipt Vessel Experience Factor (Load)

14.3 GENERAL Transportation of chemicals by tankers is usually accompanied by considerable documentation. Documentation can be even greater when trading to and from less developed countries. The vessel’s management is presented with a great deal of documentation from parties to the cargo, authorities, etc. Furthermore vessel’s management must also issues papers serving to record evidence, claims etc. Cargo is bought and sold in various units of measurement. These may be Barrels (Bbls) at 60F, Cubic metres (M3) @ 15C, Metric Tonnes in Vacuum, Metric Tonnes in Air and Long tons in Air.



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VMS/CHM/01 01 2 of 10

Other conventions of measurement exist, and the purpose of this section is to show how the vessel may deal with any system of measurement without difficulty.

14.4 ASTM TABLES In 1980, the American Society for Testing and Materials (ASTM) together with the London Institute of Petroleum (IP) and the American Petroleum Institute (API), introduced the new API/ASTM-IP Petroleum Measurement Tables (further ASTM tables). Presently the set of ASTM tables consists of 14 volumes however only a few tables are required for onboard cargo calculations. The following is the list of ASTM volumes (with description of required tables) each vessel should carry on board: For tankers carrying Petroleum Products: • • • • • •

Volume II (Tables 5B and 6B). Table 6B to be used for petroleum Products correction of volume to 60ºF against API Gravity at 60ºF. (American Measurement System). Volume VIII (Tables 53B and 54B) Table 54B to be used for Petroleum Products correction of volume to 15ºC against Density at 15ºC. (Metric Measurement System). Volume XI/XII (Tables 1-4, 8-14 and 21, 22, 26-31, 33, 34, 51, 52, 56-58). Tables for conversion between various Volume and Density Measures.

These sets of books together with ship’s Ullage Tables or Sounding tables provide everything required for calculating the quantities of oil cargoes on board the vessel.

14.5 DENSITY, RELATIVE DENSITY AND API 14.5.1 Density Density is by definition measured in a vacuum at 15C Density x volume (M³) gives metric tonnes in vacuum. Density – 0.0011 is known as “density in air”. For example: 1000M³ at 15C of density 0.8560 is 856 metric tonnes (MT) in vacuum or 854.9 MT in air. Use tables 54A or B in volumes VII and VIII. 14.5.2 Relative Density 15/4 Relative density 15/4 is the density of oil at 15C/density of fresh water at 4C. Relative density 15/4 can be treated exactly the same way as density at 15C as it is almost the same. Use table 54A or B in volumes VII or VIII or convert to API using table 3 in volume XI/XII.



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VMS/CHM/01 01 3 of 10

14.5.3 Relative Density 60/60 (SG) Relative density 60/60 is the density of cargo at 60F/density of fresh water at 60F. Convert this to density at 15C, or API using table 3 in volume XI/XII.

14.6 VOLUME REDUCTION TO STANDARD TEMPERATURE There are several standard temperatures in use throughout the industry. It is the Company policy that, except where tank calibrations are only in barrels, calculations of cargo quantity will be done using density at 15C and cubic metres as a volume measure. If the density is given at 20C, as in Brazil or Rumania, it should be converted to 15C in the following way. Product density @ 20C = 0.8764 Table 53B, Volume VIII, page 209. Call 20C “observed temperature”. Corresponding density @ 15C is 0.8798. Proceed with calculation using density @ 15C. Reduce the volume to 15C with table 54B, or 60F with table 6B as appropriate.

14.7 ULLAGE REPORTS On completion of loading and prior to commencement of discharge operations the Chief Officer together with the surveyor will check the ullage and the temperature of the relevant tanks. These two parameters are the basis for the cargo calculation and they are to be recorded in the “Ullage Report Form”. With heated cargoes, great care must be taken to establish the correct average temperature in each tank. This can only be done with electronic probe thermometers. Some cargoes however, will block the sensor of the thermometer. If this occurs, glass thermometers are to be used in preference to blocking up all the ship’s electronic thermometers. If glass thermometers have been used, a note are to be made on the Ullage Report Form. Water dips can successfully be taken in almost any heated cargo, if the sounding rod is left on the bottom for a minute, and gently worked up and down. Kolor Kut water finding paste should be used if possible, in preference to Vecom water finding paste as the Vecom paste tends to change colour in contact with suspended traces of water in the cargo, and may cause great errors in the recorded free water quantity.

14.8 SHIP’S EXPERIENCE FACTOR (SEF OR VEF) Surveyors at a load port must always be given the information to calculate the Ship’s Experience Factor or Vessel Experience Factor.



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VMS/CHM/01 01 4 of 10

14.9 (“ROUGH”) PORT/CARGO LOG The “rough”, (or working) cargo log must be kept by the officers on duty to document the loading and discharging operations. It serves to record data as a basis for the ‘Statement of Facts’ as well as all circumstances and events relevant to any dispute with the parties to the cargo. The rough cargo log is a very important document of proof in case of disagreements between the parties involved. The following entries are the minimum necessary: •

Hose connected

•

Purging times

•

Foot sample/line sample

•

Loading/discharging times

•

Loading/discharging pressures (every ½ hour)

•

For heated cargoes; temperatures

•

Blanketing times

•

Stoppages + reason

•

Special circumstances and events

•

Other relevant information.

AS THE CARGO LOG MAY BE USED IN ARBITRATION OR OTHER LEGAL ACTION THE ENTRIES SHOULD BE LEGIBLE, CHRONOLOGICAL AND NEAT.

14.10 NOTICE OF READINESS (NOR)

A Notice of Readiness (NOR) must always be provided when a vessel arrives at the port of destination. Whether the berth is occupied or not, whether the vessel is alongside or not, on arrival at the port of destination the Master must present the NOR on the appropriate form. If it is not possible to berth, for whatever reason and the vessel has to wait on the roads, the NOR must be tendered by telex, fax, e-mail or by telephone. In the latter case this must be followed by written confirmation to the agency, requesting them to provide it to the Receivers, Charterers, Terminal etc. Significant for the ‘time counting’ is the time the NOR has been tendered- and not the acceptance of the notice. The only time when NOR is not effective is when repairs have to be carried out, before the vessel can load / discharge. In such case NOR should be given immediately after the repairs have been completed. Separate NOR must be tendered for each Shipper or Receiver. When a parcel is completed at a particular berth and the next berth involving a different Shipper or Receiver is occupied, then the NOR must be tendered when the hose(s) is disconnected, at the berth where the vessel is moored.



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VMS/CHM/01 01 5 of 10

At the load port the NOR must have the amount of cargo for each parcel that the vessel can load. For example 1050 mts, but never write 1050 mts more or less owners option or similar phrases. Always state the maximum quantity the vessel can take within the quantity option agreed in the fixture on the NOR. At the discharge port the NOR must include the amount of cargo according to the B/L.

14.11 BILL OF LADING, B/L The B/L is presented to the Master by the Shipper or the Agent in the port of loading, usually three originals and one set of copies. The weight of the cargo loaded is determined by ship and shore figures. Usually the shore figures are used on the B/L. The following items have to be checked carefully before the B/L is signed: •

Cargo destination and weight

•

Bill of Lading number

•

Date of issue: always the final loading date

•

Date of charter party, as indicated in the voyage orders

•

Information regarding ship: name, nationality, name Master, etc.

•

Method of payment of freight Freight as per c/p Freight prepaid Collect freight Other

•

Correct port of discharge.

•

Cargo commingling Clause

The three original Bs/L must be signed personally by the Master and not by a rubber stamp. All other Bs/L prepared, apart from the agreed originals are to be stamped “Copy – Not negotiable”. A blank B/L must never be signed. In special circumstances – by prior agreement from the Owners – the Ship’s Agent may be authorised to sign the completed Bill on behalf of the Master. In this case clear instructions must be given by the Master to the Agent on the procedure to be followed. On all occasions however the Agent before signing the B/L must contact the Master concerned who in turn will advise if a clean B/L may signed or endorsed with the quantity in dispute or a Letter of Protest issued in lieu of clausing the Bill of Lading. If the Ship’s figures differ more than 0.5% from the Bill of lading figure, and clausing of the Bill of Lading is not acceptable to the Shipper, the Master should contact the management office for further instructions.



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VMS/CHM/01 01 6 of 10

As soon as agreement is reached on all points, all Bs/l are to be signed by the Master. Usually the Master will be provided with an original B/L, sometimes only a copy. The departure telex/e-mail to the management office should include the type of Bs/l remaining on board. A Bill of Lading endorsed with “Freight Prepaid” should never be signed without prior approval from the Owners or management office. The original Bill of Lading (or Delivery Note) covering the cargo, duly endorsed by Consignee or Receiver has to be presented to the Master prior commencement of discharge. In the port of loading the Master is often given an original B/L for the receiver of the cargo. If the Master is able to determine beyond any doubt the identity of the Receiver in the port of discharge, he may give him the B/L in exchange for a receipt. Otherwise, the original B/L is to be given to the Agent in the port of discharge in exchange for a receipt in which he is obligated to give the cargo to its rightful Receiver. If an original Bill of Lading can not be presented on arrival of the vessel the management office is to be informed immediately and the Master should act according to the instructions given. A solution could be the discharge of the cargo against the issue of a ‘Letter of Indemnity’ (LOI), provided the Owners have agreed to it. In such a letter the Charterer or Shipper guarantees to hold the vessel/owners free of responsibility for the consequences for delivering the cargo without the availability of an original B/L. Another possibility which may be considered, after approval from Owners, is for the cargo to be discharged into customs bonded storage, from which it will only be released to Receivers after the original B/L is presented or LOI received.

14.12 LETTERS OF PROTEST In order to ensure Owners claims against parties involved or to annul any claims against Owners the following protest are to be issued in the English language under certain conditions: • • • • • 14.12.1

Difference Protest Deadfreight Protest Temperature Protest Low loading or discharging Rate Protest Exceeding of maximum agreed quantity Difference Protest

Upon presentation of the B/L, the cargo weight indicated in the Bill of Lading (Shore figures) is to be compared with the ship’s ullage measurement (Ship’s figures). In case of any deviation of B/L weight from the ships figures, a difference protest is to be issued and addressed to the Shipper. The protest is usually signed ‘for receipt only’. If the Shipper is not available on board to receive the protest, the Agent has to be given the protest in exchange for a receipt stating his obligation to hand it over to the Shipper. When the difference Bill of Lading- Ship’s figures in the discharge port is more than 0.5% the surveyor will usually address an appropriate protest to the ship. This protest should always be signed



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VMS/CHM/01 01 7 of 10

‘For receipt only’. Master is not to sign any B/L which deviates more than 0.5 % from the ships figure without consultation with the management office. 14.12.2

Deadfreight Protest

This protest is the basis for Owners deadfreight claim against the Charterers, in the event that the shippers are unable to supply the quantity nominated in the Notice of Readiness. It is important that the form is filled in completely and delivered to the Shippers via the Agent as soon as it is known that the nominated quantity is not / will not be loaded. 14.12.3

Temperature Protest

Cargo loading temperature or temperature margins are agreed for cargoes requiring heating. If the temperature deviates appreciably from the agreed levels (usually +/- 10% of the allowed temperature) a ‘temperature protest’ is to be issued against the Shipper. If the maximum temperature agreed to is exceeded (e.g. for phenol) even minimum excess temperature can not be accepted, depending on the product and conditions of stowage. A ‘temperature protest’ is to be issued. The management office is to be kept informed. The Receivers will usually protest when the cargo temperature is determined as too low or too high by the surveyor. Discharge temperatures of cargoes –MARPOL category ‘B’ and ‘C’ should be at least 5 or 10°C. above the melting point of the product in each case, but always within the heating orders as stipulated by the Shipper and/or Owners so as to avoid the prewash obligation. In case of cargoes requiring heating, the heating orders of the Shipper or Owners must be followed to avoid protests and delays in the port of discharge. Note that overheating can damage some cargoes (Phenol, HMD). 14.12.4

Low loading or discharging rate protest.

Depending on the total time for loading, a suitable protest is to be directed to the Shipper if the loading rate is much too slow. Some charter parties do have a minimum loading rate. In this case the operator will inform you regarding the minimum loading rate. A discharge rate (m3/h) is normally agreed in the charter party. The Receiver will lodge a ‘discharge rate protest’, if the actual rate seems too slow to him. All remarks have to be entered by the Master in the protest that could improve the position of Owners in a possible claim. Such as, but not limited to the following: •

Back pressure too high

•

Length of the landline

•

Small diameter of the landline

•

Difference in height between ship and land tank

•

Product properties(viscosity)

•

In case of heated cargoes: insulation of land line


• 14.12.5


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VMS/CHM/01 01 8 of 10

Shore stoppages. Exceeding the maximum agreed quantity

If the maximum agreed cargo quantity is exceeded (min/max, upper margin limit) by no more than 1% or 2 mts, this can be accepted. If the limit is exceeded, the management office must be informed immediately that necessary steps can be taken. The following solutions are feasible: •

Protest

•

Pumping back the excess cargo.

14.13 STATEMENT OF FACTS On the ‘Statement of facts’ all relevant facts and times concerning loading / discharging are to be recorded. The statement is the basis for laytime counting and has to be signed by the Shipper’s - or Receiver’s representative (usually the Loading Master) the Master and the Agent. A completely signed ‘Statement of facts’ is effective evidence. It is important that the statement contains all conditions and events that have a positive influence on time counting. A ‘Statement of facts’ must contain, depending on the situation, the following data, events or conditions, stating local times: • • • • • • • • • • • • • • • • • • • • • • • • •

Name of the vessel Voyage number Loading/discharge port, berth End of seapassage Arrival roads Reasons for delay on the roads (if awaiting departure of other vessel(s) state name(s) of vessel(s)) Pilot boarded Passing breakwater First line ashore Arrival berth(name) NOR tendered/accepted Draft on arrival fore/aft Ullages taken Samples taken Tanks inspected/accepted Hose connected Commenced loading /discharging Completed loading/discharging Ullages/samples taken Tanks accepted dry and empty Hoses disconnected Cargo documents on board Draft on departure fore/aft Pilot on board Departure berth


• • • • • •


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VMS/CHM/01 01 9 of 10

Pilot dropped Start of seapassage Loaded grade and quantity as per B/L, ship’s figures Bunkers (on arrival, on sailing and taken) Tugs used Remarks (e.g. purging times, stoppages).

The Agent has to be instructed to convey all relevant documents including ‘Statement of facts’ and to fax/ e-mail those important documents to the management office immediately.

14.14 DRY TANK CERTIFICATE When the tanks are empty the surveyor will check the tank in question and issue a ‘Empty tank’ or ‘Dry Tank’ certificate. The issue of this certificate constitutes the commercial and legal termination of the obligations of the vessel to the contractual parties concerned.

14.15 OTHER DOCUMENTS Depending on the loading and discharge port, the Shipper, surveyor, customs, authorities etc. provide various documents to be conveyed to the Receiver, to the Agent etc. in the port of discharge. • • • • • • • • • • • • • •

Cargo quality certificate (analysis report) Cargo quantity certificate Certificate of origin Cleanliness report Heating instructions Inhibitor certificate Manifest Receipt of documents Ship’s experience factor Tank history Ullage report Sailing permit Sample receipt Custom papers

The papers destined for the Receivers are given to the Loading Master or agent in the port of discharge against receipt.

14.16 DEPARTURE TELEX/FAX/E-MAIL A departure telex/fax/e-mail is to be sent to the management office. All information contained in the “Statement of facts” is to be included. The “Statement of facts” should also contain the following data: • •

Next port and ETA Bunkers on departure


• • • • •

Bunkers taken in the port of departure Final stowage plan If Protests issued If Protests received Original Bs/L on board : yes or no


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VMS/CHM/01 01 10 of 10

CHEMICAL TANKER MANUAL SECTION 15 – MAINTENANCE ROUTINES


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15. MAINTENANCE ROUTINES 15.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section. Publication

Location

Equipment Manufacturers Instruction Manuals International Safety Guide for Oil Tankers and Terminals (ISGOTT) CFR 33 parts 125 to 199

Chief Engineer Chief Officer Master

15.2 COMPANY FORMS The following Company Forms are to be used in conjunction with this section. Company Form No TNK 09

Title Inert Gas Log

15.3 MAINTENANCE ROUTINES Within this particular section maintenance routines are required to maintain the cargo equipment operational. The Master is responsible for ensuring that these are carried out at the specified intervals described with this manual. For those vessels which have a computerised Planned Maintenance System this work is to be recorded electronically and a print out provided for quick access for any inspector who required this information. The following items are to be contained in the maintenance records – Item

Frequency

Reference

Electrical bonding check on transfer hoses Electrical bonding check on portable tank cleaning hoses

Each operation 3 Months

3.31.3 13.11/11.8

Pressure testing of Pressure testing of piping (1.5 x WP). Pressure testing of Pressure testing of pressure

12 Months

4.28

12 months 6 Months Prior to each discharge

4.29.2 7.5 11.9

Air pressure testing of sea and overboard valves

Each operation

3.25/4.29.1

Pump trips and emergency shutdowns

Each operation

4.14/8.6

transfer hoses cargo, COW, ballast and bunker heating coils cargo and COW lines to working



: : :


Item

Frequency

Reference

Cargo and ballast pump safety devices

Each voyage

13.10

Function testing and pressure testing of cargo valves

6 Months

4.29

Each operation Manufacturers instructions Weekly

9.9/9.9 9.9

Each operation Each operation

13.14 13.14

Purging of submersible pumps

Before/after each operation

10.9

Checking of mast riser sumps Inspection and examination of cargo, ballast and void spaces

Each operation 6 Months

7.5

Run of test conditions of loading computer

3 Months

13.2

Overhaul and cleaning of P/V valves Inspection of flame screens within cargo systems Inspection of flame screens within ballast/bunker systems P/V breakers

6 Months 3 Months

13.3 13.4 13.4 13.15

Deck Seals I.G. Non return valves

6 Months Manufacturers instructions 12 Months 12 Months

Overhaul and inspection of tank gauging equipment

6 Months

13.7

Opening up and cleaning of Cargo Pump strainers Opening up and cleaning of stripping pump strainers Opening up and cleaning of ballast pump strainers

6 Months Each voyage 12 Months

13.10 13.10 13.10

Check of tank cleaning machines

3 Months

13.12

Inert gas safety devices checks and operational tests Inert gas system inspection and maintenance including scrubber Test of pumproom bilge alarms Test of cargo and ballast tank high level alarms and sirens Test of cargo tank overfill alarms and sirens

13.8

13.6/9.9.1 13.6

Calibration checks on portable gas measuring equipment (Recorded in Safety Set) Calibration checks on fixed gas measuring equipment Calibration checks on pressure gauges Calibration and test run of ODME Calibration check of hermetic temperature functions Annual independent calibration of hermetic gauges

2 Months

13.13

2 Months 12 Months Monthly Each operation 12 Months

13.13 13.14 13.7 13.18 13.18

Cleaning of tank radar systems transmitters

Each operation

13.16



Item

Frequency

Mooring winch brake testing

12 Months

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Reference

CHEMICAL TANKER MANUAL SECTION 16 – CARGO COMPATABILITY


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16. CARGO COMPATABILITY 16.1 REFERENCE PUBLICATIONS The following reference publications are to be read in conjunction with this section. Publication

Location

US Coastguard 46 CFR part 150

Master

16.2 EXPLANATION OF CARGO COMPATIBILITY CHART DEFINITION OF HAZARDOUS REACTION - As a first approximation, a mixture of two cargoes is considered hazardous when, under specified condition, the temperature rise of the mixture exceeds 25o C or a gas is evolved. It is possible for the reaction of two cargoes to produce a product that is significantly more flammable or toxic than the original cargoes even though the reaction is non-hazardous from temperature or pressure considerations. Chart format - There are different degrees of reactivity among the various cargoes. Many of them are relatively non-reactive: For example, aromatic hydrocarbons or paraffins. Others will form hazardous combinations with many groups: For example, the inorganic acids. The cargo groups in the compatibility chart are separated into two categories: 1 through 22 are "Reactive Groups" and 30 through 43 are "Cargo Groups". Left unassigned and available for future expansion are Groups 23 through 29 and those past 43. Reactive Groups contain products which are chemically the most reactive; dangerous combinations may result between members of different Reactive Groups and between members of Reactive Groups and Cargo Groups. Products assigned to Cargo Groups, however, are much less reactive; dangerous combinations involving these can be formed only with members of certain Reactive Groups. Cargo Groups do not react hazardously with one another.

16.3 USING THE COMPATABILITY CHART The following procedure explains how the compatibility chart should be used to find compatibility information: 1. Determine the group numbers of the two cargoes by referring to the alphabetical listing of cargoes and the corresponding groups. Many cargoes are listed under their parent names: unless otherwise indicated, isomers or mixtures of isomers of a particular cargo are assigned to the same group. For example, to find the group number for Isobutyl Alcohol, look under the parent name Butyl Alcohol Similarly, the group number for para-Xylene is found under the entry Xylene. If a cargo cannot be found in the listing, contact the Coast Guard for a group determination (see CFR § 150.140).

CHEMICAL TANKER MANUAL SECTION 16 – CARGO COMPATABILITY


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2. If both group numbers are between 30 and 43 inclusive, the products are compatible and the chart need not be used. 3. If both group numbers do not fall between 30 and 43 inclusive, locate one of the numbers on the left of the chart (Cargo Groups) and the other across the top (Reactive Groups). [Note that if a group number is between 30 and 43, it can only be found on the left side of the chart]. The box formed by the intersection of the column and row containing the two numbers will contain one of the following: (a) Blank - The two cargoes are compatible. (b) "X" - The two cargoes are not compatible [Note that reactivity may vary among the group members. Note if the products in question are referenced by a footnote which indicates that exceptions exist, then refer to in Appendix I. Unless the combination is specifically mentioned in Appendix I, it is compatible.

16.4 COMPATABILITY CHART Please refer to US Coast Guard 46 CFR Part 150

VShips - Chemical Tanker Manual - 2004

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