Underground Undergr ound Optimization
Undergrou nderground nd Opti Optimiza mizatio tion n Solu Solutio tions ns Mineable Reserves Optimizer (MRO) Determines the optimal envelopes envelopes within which stopes should be designed
Mineable Shape Optimizer (MSO) Automatically produces produces optimized stope stope designs
Decline Optimizer (MLO) Produces optimal decline designs through a set of points
Schedule Optimizer Tool (SOT) Optimizes mining sequence and schedule to increase NPV
Reliably estimating estimating how h ow many tonnes can be mined, at what grade and at what time, based on practical mining considerations, is a critical part of every resource evaluation exercise or feasibility study .
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Undergrou nderground nd Opti Optimiza mizatio tion n Solu Solutio tions ns Mineable Reserves Optimizer (MRO) Determines the optimal envelopes envelopes within which stopes should be designed
Mineable Shape Optimizer (MSO) Automatically produces produces optimized stope stope designs
Decline Optimizer (MLO) Produces optimal decline designs through a set of points
Schedule Optimizer Tool (SOT) Optimizes mining sequence and schedule to increase NPV
Reliably estimating estimating how h ow many tonnes can be mined, at what grade and at what time, based on practical mining considerations, is a critical part of every resource evaluation exercise or feasibility study .
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Mineable Reserves Optimizer Floating Stope™ Optimization
Min ine eabl ble e Re Reserve serves s Opt ptim imize izerr - MRO Easily determine the geometry and sequence of extraction for the best economic stopes. Tonnage x Grade Curves ) t 1800000 ( s e n n o 1600000 T
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10 1400000
1200000
) t / g ( e d a r G e g a r e v A
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1000000 6 800000
600000
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400000 2 200000
0
0 0 T on on ne s x H ea dG ra ra de
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4 A ve ve ra ge Gr ad e x He He ad G ra ra de
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8 D li ut io n
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12 Head Grade (g/t)
MRO is ideal for preliminary underground reserve estimation estimation
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MRO – How doe do es it w ork? MRO uses a methodology based on the Floating Stope
™
algorithm to float a Minimum Mining Unit shape
throughout a resource model to determine a mineable reserve defined by Mineable Envelopes . Floating Stope : The MRO algorithm that “floats” a Minimum Mining Unit through a ™
geological model, testing whether it is economic at each location. Minimum Mining Unit : A discrete shape that represents the smallest volume of rock that can
be practically mined. Mineable Envelope: A contiguous volume of material representing the locations where the
Minimum Mining Unit was economic, according to th e operational constraints of the study.
MRO Defines, Evaluat Evaluates es and Sequences Mineable Reserves
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MRO – Optimization Controls Minimum Mining Unit (MMU) The MMU defines the smallest volume and shape that is practical to mine. This can be defined as a 3D rectangular block or it can defined as a set of multiple blocks created from a wireframe model. For example, stopes can be modelled with sloping walls and irregular crosssections.
Optimization Criteria The optimizer identifies volumes in the model that not only meet the minimum shape and size constraints, but are also optimized to either: Maximize ore tonnes Maximize grade Maximize contained metal Maximize accumulated value (eg dollars) Maximize the value of the deposit for a given head grade
Additional Constraints Minimum head grade to define mineable envelope. Define maximum waste : ore ratio. Model either selective or bulk mining.
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MRO Case Management Each optimization run allows several parameters to be specified. The MRO user interface includes options to assist in the selection and organization of these parameters.
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Sensitivity analyses can be undertaken easily and the alternative stope envelopes can be analyzed to provide reserve information
Sequencing of Envelopes MRO’s Sequencer decides the best order in which the envelopes should be extracted and the path of extraction. This takes account of both the positive value defined by the g rade or dollar value of the material and also the fixed and variable costs of mining, transportation and processing.
The sequencer outputs links that identify the order of mining that will maximize value
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MRO – Also for Open Pits! MRO can also automatically optimize the identification of mineable blocks within benches. Complex cut-off rules with multiple variables can be built into the MRO logics. Ore selection can be based on profit rather than just grade.
Optimization of grade control lines can significantly reduce ore loss and waste dilution whilst considering mining selectivity.
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MRO – Open Pits In this example dig lines within a blast have been determined to identify where material should be sent to maximize value. Economic and other rules such as processing characteristics have been taken into account to maximize the value of the blast whilst hon ouring mining and equipment constraints.
In this second example mineable blocks on a pit bench have been automatically identified according to grade bins.
MRO can maximize value from open pit blasts by objectively determining optimal dig lines
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MRO - Summary
MRO provides a fast, objective and flexible way of estimating the tonnage that can be mined from a resource and at what grade, based on practical mining considerations.
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Mineable Shape Optimizer Objectively Optimized Stope Designs
Mineable Shape Optimizer (MSO) Automatically produce objective optimal stope designs within an underground resource
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Mineable Shape Optimizer (MSO) MSO can: •
Generate final individual stope designs within a resource model
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Handle massive and narrow dipping orebodies, and integrate with tools for ‘Dynamic Anisotropy’ allowing the modelling of complex orebodies
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Correctly model waste pillar geometry, and apply internal and wall dilution rules
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Report attributes for each stope including reserve category, geological domain, ore processing type and others, based on parameters in the input block model. MSO is a true optimization tool maximizing the value of recovered ore given the stope geometry and design rules
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MSO Background MSO developed as part of AMIRA “PRIMO” and “SIRUS” Projects Researchers include Alford Mining Systems (AMS) and AMC Consultants
MSO v1.0 released in 2009 by Datamine MSO v1.1 released in January 2012 by Datamine (CAE Mining) UGSO (v2) to be released in 2014 by Datamine
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MSO Data Inputs Block model with grades, value, density and other attributes in orthogonal or rotated coordinates Prototype for stope annealing with orientation, stope shape, costs, development etc. Geological control wireframes
Outputs Stope wireframes Section and plan design strings Reserves report Runs are configured using a clear user interface that includes case management tools
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MSO Examples
Block Model
Practical Mining Shapes Optimized Stopes
Geological Control
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MSO Examples
This animation shows a vertical section through stopes created within a narrow vein orebody.
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The 3D optimization objectively determines whether to separate stopes or combine with waste to maximize value whilst honouring mining constraints.
MSO Practical Stope Shapes and Benefits Internal pillar width, metal content & dilution
In these areas the value of the ore does not carry the cost of mining a single stope that includes the waste. The minimum pillar width p revents two separate stopes being mined. MSO has determined that the green stopes are the optimal design choice.
Minimum Pillar Width In this area although the red stope design appears to contain a higher volume of ore the green stope is in fact the optimal choice.
Red Stope = 946 Oz (32% Dilution below COG) Green Stope = 1,040 Oz (4.4% Dilution below COG)
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MSO – Accessible Reserves
Stope Reserves can be interrogated immediately and further analysed using other Datamine tools
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How It Works Works within user-defined framework in XZ, YZ, XY or YX orientations Algorithm works within each “tube” or “quad”
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How It Works Works within user-defined framework in XZ, YZ, XY or YX orientations Algorithm works within each “tube”
Three Step Process 1. Create slices within each tube at user-defined strike and dip 2. From the slices, find an economic seed shape “
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3. Anneal the seed shape to find the optimised stope shape
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The Stope Shape Annealing Process MSO works by: • Identifying the approximate size, shape and location of the orebody • Generating outlines by parameterizing the stope shape • Linking the sections to create a wireframe shape for evaluation • Using an annealing procedure to take the ‘seed’ stope shapes and mould them into the final stope shape, honouring stope and pillar geometry • Generating stopes, sub-stopes and depleted volumes as wireframes, section strings and reporting tonnes and grade The approach mimics an engineer’s approach to the design on adjacent 3D sections, “rubber banding” the outline to improve the evaluated result.
MSO provides an objective and reproducible full 3D shape optimization
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Previous Versions MSO v1.0 Creates optimised stopes within a fixed-interval vertical (XZ or YZ) framework based on maximising either value or grade Users define the minimum stope width, minimum pillar width, as well as near- and farwall dilution Outputs stope wireframes plus horizontal and vertical stope strings Outputs a report on the optimised stopes Ideal for sub-vertical mineral deposits
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Previous Versions MSO v1.1 Adds XY and YX framework options for sub-horizontal (flat-lying) deposits Adds more flexibility in defining sub-shapes Adds an alternative method for stope evaluation Released in January along with Studio 3 MR21 and Studio 5D Planner
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Next Version UGSO (MSO v2.0) Cloud-based optimization Many additional stope framework options: can define rib and sill pillars, primarysecondary stope arrangements and variable level spacing intervals Smoothing and splitting of output shapes Output centre shape strings More optimisation parameters Boundaries and structures Integrated data management, reporting, analysis and sensitivity
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UGSO – Stope Framework Options UGSO (v2) v1.0 Additional methods coming in the future
v1.1
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Vertical Frameworks (XZ, YZ) Irregular Levels Gradient strings
Regular Intervals
Irregular Sections Ore Development Strings
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OreDev-Gradient strings
Vertical Frameworks (XZ, YZ) User Defined “ Tube” Dimensions
Rectangular
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Quadrilateral
Transverse Section (XZ, YZ)
Optimize Level Intervals (by section)
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Section Level Strings
Horizontal Frameworks (XY, YX) Irregular Intervals Contour Strings
Horizon-Contour Strings
Regular Intervals
Irregular strike drives
Irregular dip drives
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Prism Method
Defined range of shapes
Discrete shapes
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Optimized shape combination
UGSO Enhancements – Area of Interest Define Area of Interest and Framework Orientation dynamically with realtime 3D visualization
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UGSO Enhancements – Stope Layout New “Builder ” allows users to easily and intuitively define the arrangement of levels, stopes and pillars
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UGSO Enhancements – Cut-Off Grade Cutoff grade is a “boundary ” descriptor Head grade is a “volume” descriptor One or both can be supplied in UGSO The values can be supplied as either: A fixed value A value from the block model A table which allows the value used to be a function of the width or height dimension or tonnage of the stope
The last option allows the software to dynamically choose between bulk and selective mining by making the cutoff and head grade a function of the stope size
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UGSO Enhancements – Boundaries Exclusion Do not include this material in a stope
Stand-Off Distance Do not include this material or material with a surrounding distance in a stope
Inclusion Only allow stopes within this material
Report Exclusion Exclude this material from the reported stope
Mixing A stope cannot include material from more than one zone
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UGSO Enhancements – Structure Geological structure can be a cause of overbreak into a stope that can and should be planned for Structure can be modelled as wireframe surfaces If the seed or annealed stope shape is within a nominated distance of this wireframe, the stope shape is adjusted (“snaps”) to the wireframe surface The stope optimizer will make an evaluation decision to determine if expanded stope is to be accepted
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UGSO Enhancements – Post-Processing Three new functions are provided to post-process the output from UGSO:
Split Where the ore width is greater than the maximum stope width Rules to allow splitting on a regular grid, centred, distance from walls, etc.
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UGSO Enhancements – Post-Processing Three new functions are provided to post-process the output from UGSO: Smooth Stopes are optimized independently by plan and section Smoothing is an additional annealing step to eliminate gaps at the corners of stopes horizontally and vertically Substope corners are also adjusted if adjacent to a full stope corner
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UGSO Enhancements – Post-Processing Three new functions are provided to post-process the output from UGSO: Merge Merge may be used to define a maximum that is determined by geotechnical stability (e.g. not to exceed a hydraulic radius criteria). To define a minimum that is determined by economics or mining practicalities (e.g. combining stopeshapes that required small intervals due to variability of the orebody) To define a regularised extraction sequence for stope-shapes (e.g. vertical stacking of primary and secondary stopes)
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UGSO Enhancements – Sensitivity Use the power of cloud computing to conduct comprehensive sensitivity analyses on your data
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UGSO Enhancements – Reporting Summit reporting and analysis tools eliminate the need to manually analyse results
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Comparison of Manual, MRO and MSO Manually created mining shapes Studio 5D Planner Studio 3
Mineable Reserves Optimizer (MRO) Mineable Shape Optimizer (MSO) Ian Lipchak (2009)
Manually Created Shapes Time-consuming for initial high-level assessment Tends to be more detailed (since you are spending the time to create the shapes anyway) Works well as the “detailed design stage” following the use of MSO
Mineable Reserves Optimizer Less detailed than MSO Floating Stope” not as versatile “
Different methodology creates Mineable Envelopes
Mineable Shape Optimiser Produces wireframe solids and strings Takes orebody geometry into account Very fast and easy to use
Comparison Used cut-off grade of 2 g/t Au Manual shapes (detailed): sill and rib pillars MSO: sill pillars but not rib pillars MRO: no pillars and used small MMU Method
Tonnes
Grade (g/t)
Grams Au
MSO
581,678
8.91
5,184,467
MRO
898,447
4.78
4,291,881
Manual
350,071
9.35
3,273,167
Comparison
Using MSO with MRO It is possible to run MSO on an MRO output model Two steps: 1.
Run MRO to produce mineable envelopes that meet certain constraints and criteria
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Run MSO to generate stope shapes around the mineable envelopes
Decline Optimizer Automatically-Generated Optimal Declines
Decline Optimizer Rapidly assess alternative designs for underground access
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Decline Optimizer Using either a stope design or orebody envelope define the access points through which the decline must pass
Convert the points to a string that will control the decline path
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Decline Optimizer – Controls Radius and Gradient Either fixed values or Min and Max Allowable Offsets X, Y and Z offsets that can be applied in any combination of directions defining a flexibility cuboid Directional Control Initial and Final Azimuths, minimum straight portions value, end of decline direction Access Point Gradient control and flat areas for access points Exclusion Zones Exclusion zones such as an optimised stope model or string outlines
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Decline Optimizer – Minimization Optimization Methods §
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Minimize Total Path Length Minimize Arc Length Minimize Deviation from Preferred Orientations Minimize Total Cost Specify the Ramp/Drive/Haulage cost per metre
All of these can be combined by defining a weight for each component
Decline Optimization assists with rapid engineering at the analysis stages of a project as well as being a valuable aid to subsequent more detailed designs
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