Distillation ChemCAD

Group: 8Cesar CastroJacky TsaiDung Phan

Vivi He

CHBE 446February 13, 2015

Outline/Agenda

• Types of Distillation Columns in ChemCAD• Steps for doing distillation in ChemCAD– 1 set up workspace– 2 choose component– 3 thermodynamic setting– 4 feed stream data– 5 distillation column data– 6 RUN and report streams

• Plots

Types of Distillation Column in ChemCAD

• There are three rigorous steady state distillation models in CHEMCAD: – scds (simultaneous correction distillation)– tower (Inside-out method)– tower+ (tower unit with additional in/out connections).

• The shor column is not a rigorous column. The shor column uses the Fenske-Underwood-Giliand model to calculate separations.

• There is also one Batch column

Which to choose?

• scds column: activity coefficient K values • tower column: equations of state. • tower+ column: petroleum models. • shor column: generally used only in education,

and should not be used to model an actual column.

Recommendations

Step one: set up in Workspace

This area is your Workspace

Step two: choose components

1

2

3

Step two cont.

Step two cont.

Step three: Thermodynamic setting

http://www.chemstations.com/content/documents/Technical_Articles/thermo.pdf

This website (also listed in Design course webpage) explainsthermodynamic models in detail

Thermodynamic Model

Step four: feed stream data

1

3

2 Choose two to enter

Data shown after Flash

Step five: distillation column data

Step five cont.

Step six: RUN and report

• You can get your stream composition and properties reports afterwards

Example: stream composition report

Plots

Example: Txy-plot

Example: xy-plot

Reference

• http://home.anadolu.edu.tr/~skaytako/web_malzemeleri/DISTILLATION%20CONVERGENCE.pdf