Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation This tutorial will show the steps necessary to resolver an energy balance on Aspen Plus. The following example will be used: Problem statement: 1 mol/min propane gas undergoes a change of 5 bar and 105°C to 25 bar and 190°C. Compute the energy added. (1) Propane T = 105°C P = 5 bar
(2) Propane T = 190°C P = 25 bar Q=?
Note that this problem was solve with the application of Peng-Robinson Equation and the result was Q = 7315 J/min. Now we solve this problem using Aspen Plus Simulator. 1. Open a blank simulation write the name and define a unit system with the necessary units. 2. Add a Heater Model on flowsheet area.
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3. To add the streams to Heater Block, click on Material STREAMS, now the block has two red streams (indispensable streams) and a blue stream (optional stream).
Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation 4. Connect the input stream in the red input and output stream in the red output.
5. The flowsheet is complete, now is necessary specify the compounds and operation conditions. Click Next bottom. Click Next Bottom
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6. Add the chemical compounds; Click Find, write the name of compound and click Find now, Add, Close. In this case, only is necessary add propane. Clic Next bottom.
Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation
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Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation 7. Select the property methods, In this case is Peng-Robinson. Click Next bottom.
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8. Specify the initial conditions (T = 105 °C and P = 5 bar and 1 mol/min). Because there is only propane, the mol fraction or mass fraction is 1. Click Next bottom.
9. Specify the final conditions (T = 190 °C and P = 25 bar). These values are the same in the unit equipment and the output stream. Click Next bottom.
Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation 10. Run the simulation, click Aceptar.
11. To visualize the results (heat duty) click on blue folder.
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12. In the Block folder, there are the results of energy balance. (note: it is possible change the units in the results).
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Q
The results are very similar to the pass result (Q=7216 J/min).
Industrial Chemical Process Simulation Eng. Javier Ramiro Morales Hernandez Eng. Misael González Macias
Energy balance using Aspen Simulation 13. If you need to see the properties stream, click in Streams folder and explore the results. References 1. Lang, Jim. Design Procedure for Heat Exchangers on AspenPlus Software Design Manual. 1999. 2. J. Richard Elliott and Carl T. Lira. Introductory Chemical Engineering Thermodynamics. Prentice Hall PTR. 1999. 3. Warren D. Seider, J. D. Seader and Daniel R. Lewin. Product and Process Design Principles: Synthesis, Analysis and Evaluation. John Wiley and Sons, Inc. 1999. 4. Lewin, D.R., W.D. Seider, J.D. Seader, E. Dassau, J. Golbert, G. Zaiats, D. Schweitzer, and D. Goldberg, Using Process Simulators in Chemical Engineering: A Multimedia Guide for the Core Curriculum,” John Wiley and Sons, Inc. 2001. 5. Aspen Technology, Inc.
