611 401 Computer Applications in Materials Engineering การประยุกต์ใช้คอมพิวเตอร์ ในงานวิศวกรรมวัสดุ

1. 611 401 Computer Applications in Materials Engineering การประยุกต์ใช้คอมพิวเตอร์ ในงานวิศวกรรมวัสดุ

2. Process Simulation Steam line ‘cat-crackergas separation’ example in ChemCAD 5.2, Chemstation, Inc.

3. Process Simulation Unit Operation ‘cat-crackergas separation’ example in ChemCAD 5.2, Chemstation, Inc.

4. Mathematical Modeling and Simulation SCALE … Microscale force balance in control volume of fluid heat balance at surface inside unit operation Macroscale material and energy balance around unit Processes material and energy balance around section of process Law of conservation Mass and Material Balances (bulk mass and mole, chemical reaction) Energy and Heat Balances (enthalpy of bulk) Force or Momentum Heat transfer (conductive, convective and radiation) Mass transfer (specie moment, chemical kinetic)

5. Calculation Step in Chemical Engineering System and Environment Input and Output (flowchart) Steam in/out: flowrate, temperature, physical and chemical properties, composition etc. Basis and assumptions (also unit system) Continuity equations mass, energy, force, specie etc. Modeling of static/dynamic behavior Steady state or non-steady state (transient) Solving method Analytical solution or Numerical Method Simulation, validation and optimization

6. Continuity equation Flowchart: • Total mass balance: Assumption: most of chemical processes has no nuclear reaction

7. Assumptions: Thermodynamics: Equation of state (gas phase) Phase change Equilibrium state Heat/Enthalpy change Heat of solution, reaction, phase change Reaction kinetics: % conversion Reaction mechanism Exothermic or endothermic reaction Energy efficiency: % efficiency

8. Steady State Modeling Case A – Heat exchanger (HE_01):System scale (Macroscale) Basis:Fh kg/hr Fh , Th,out Assumption: %80 energy efficiency System Fs , Ts,out Continuity Eq. of enthalpy (input=output) for heating steam Fs , Ts,in Heat capacity is constant Analogy with heating steam Fh , Th,in %80 efficiency ** Continuity Eq. of enthalpy (input=output) for heat exchanger

9. Steady State Modeling Case A – Heat exchanger (HE_01):System scale (Macroscale) Fh , Th,out System Fs , Ts,out Calculation: Fs , Ts,in Fh , Th,in

10. Steady State Modeling Case A – Heat exchanger (HE_01): Microscale / Macroscale Basis:Fh kg/hr Assumption: heat transfer through plate %100 efficiency System

11. Steady State Modeling 50 °C 52 °C 54 °C 56 °C 58 °C 0 60 °C Conductive heat transfer Convective heat transfer Case A – Heat exchanger (HE_01): Microscale System

12. Steady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) FA , TA,in FB , TB,in Basis:FA= 500 kg/hr(%10 w/w A) FB= 500 kg/hr (%10 w/w B) System Assumption:60% conversion Calculation: (reaction in moles) Comp wt Mwt Input Output FP , Ts,out A 50 25 2 0.8 B 50 10 5 1.0 Hrxn A + 2B  C C 1.2

13. Reaction Kinetic Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) Basis:FA= 500 kg/hr(%10 w/w A) FB= 500 kg/hr (%10 w/w B) Assumption: k A + 2B  C

14. Activity Solving numerically by using finite difference method Calculate concentration of A, B and C in batch reactor

15. Activity Case B – Continuous Stirrer Tank Reactor (CSTR_01)

16. Activity Case B – Continuous Stirrer Tank Reactor (CSTR_01)

17. Activity Case B – Continuous Stirrer Tank Reactor (CSTR_01)

18. Activity Case B – Continuous Stirrer Tank Reactor (CSTR_01)

19. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) mass energy A B C Remarks: Check unit for all terms !!!

20. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) Variables 1. Volume of liquid in reactor (Vr) 2. Temperature in reactor (Tr) 3. Conc. of A, B and C 4. Density (equal water for dilute solution) 5. Heat Capacity (assume as a constant)

21. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) Reaction kinetics Initial conditions Flowrate & Fluid in reactor

22. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01) mass reaction energy A B C Remarks: Check unit for all terms !!!

23. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01)

24. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01)

25. Unsteady State Modeling Case B – Continuous Stirrer Tank Reactor (CSTR_01)

26. HomeWork (1) A + B  C C + A  D (2)A + B C

27. Process Simulation Case C – HF Production CaF2(s) + H2SO4 (aq) → CaSO4(s) + 2 HF(g) Gas Fluorspar 200 kg/hr AB1 AB2 AB3 CaF2%15 HF(g) REACTOR H2O H2O H2O CaF2 (s) < %3, H2SO4(aq) CaSO4 (s) H2SO4%27 HF(aq) % 70 % 40 % 5 xkg/hr 5% exceed

28. Process Simulation system Case C – HF Production Objective: calculate production yield Basis:200 kg/hr of Fluorspar Assumption: 1. Fluorospar(CaF2 15%) 2. H2SO4 5% exceed 3. CaF2 < 3% CaF2(s) + H2SO4 (aq) → CaSO4(s) + 2 HF(g) Substances: CaF2, H2SO4, CaSO4, HF , H2O Unknown: %conversion (kinetic)

29. Process Simulation

30. Activity Case C – HF Production CaF2(s) + H2SO4 (aq) → CaSO4(s) + 2 HF(g) Excel file for (1) calculating amount of water which will use for absorb 70, 25 and 5% of total HF at AB1, AB2, AB3 respectively (2) feed rate of sulfuric acid and the production yield