CHEMCAD Distillation

1. CHEMCAD Distillation David Weglein Savannah Green Heather Cook Michael Wellen

3. Recently used files Tabs to access other things

4. Data tree from simulation

5. Access VBA programming

6. Errors and warnings, run trace, and notes

7. Palette

8. Workspace

9. Checklist

10. What if… • You have a Japanese client working in Yen, who liked everything about the metric scale except length measurements, thinks the Rankine scale is underrated, and likes his vapor density in lb/ft3 • No problem!

11. Checklist

12. Choosing a Thermodynamic Model

13. Recommendations Gas Phase Only Ideal Solution Non-ideal Solution

14. Checking Equilibrium Data

16. CHEMCAD Distillation Columns • 4 types of columns, differ in: • What algorithm they use • What information load they can handle • What parameters you can find from simulation

17. #1 – Shortcut Column • Uses Fenske-Underwood method • One feed, bottoms and distillate • Typically used as a way to get rough estimates • Reboiler/condenser duties, number of theoretical stages, optimum feed location, fractional recoveries. • Industrial users will (should) not use this one

18. #2 - SCDS • Simultaneous Correction Distillation System • Uses a “simultaneous correction” algorithm • Can do reactive distillation, mass transfer distillation (packing) • Stable with non-ideal thermodynamics • Handles a large number of stages • Multiple feeds, side stream possible • In addition to what the SHOR column can do, can also do mass transfer and tray efficiency • Commonly used

19. #3 - Tower • “Inside-out algorithm” • Used for large number of components, small number of stages • Can do dynamic (non-steady-state) simulations • No efficiencies, mass transfer, or reactive distillation • Used more for hydrocarbons

20. #4 – Tower+ • Used for crude oil • Complex columns

21. Recommendations

22. Demo