DISTILLATION/ABSORPTION COLUMN DESIGN

1 DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN I1800 or earlier NowDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IDistillation AbsorptionDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IPacked Tower tray towerDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsHeat Integrated distillation columns (HIDiC) DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsPetroleum FractionationDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsPervaporation distillationDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsDouble EffectDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsPressure Swing DistillationDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex columns Multicomponent casesSimple Sequences DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex columns Multicomponent casesSimple

2 SequencesDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IComplex ColumnsPetlyuk Colums (circa 1960) Divided wall columnChE 4253 - DESIGN IChE 4253 - DESIGN IDISTILLATION/ absorption COLUMN DESIGNC omplex columns Multicomponent casesComplex SequencesDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IAbsorber/stripper typical arrangement. DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IDistillation ControlDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IBINARY SYSTEMS: Use McCabe ThieleGiven xBandxD calculate RR, #trays, Feed tray , D, B DesignGiven xD andRR (for fixed #trays and feed tray ) xB, D, B OperationsGiven 2operating values (for fixed #trays and feed tray ) the rest OperationsDISTILLATION/ absorption COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IMULTICOMPONENT SYSTEMS : Use Computers!

3 !!Degree of Freedom= Number of unknowns Number of equations One per each condenser, reboiler or draw. See notes. 2 123456789101T1S1S2S3S423456789110T1S1S2S 3 DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IMULTICOMPONENT SYSTEMS : Use Pro IICase 2: You know number of trays and feed tray location You need to fix variables or add equations. Add Equations (The easiest ), Reflux ratio and Recovery ratio Fix variables, Compositions, temperatures, flows, etc. DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IMULTICOMPONENT SYSTEMS :Case 2: You know nothing, not even the number of trays needed.

4 Use Fenske-Underwood Gilliland (see Separation Class Book) to get an ideaPro II has this shortcut .. or if you are too lazy use Pro II as follows1. Do not try blindly specs and number of trays. it won t work most of the If you have many components do not include them all at the beginning. start with afew of the most abundant Put an adiabatic flash first. if the feed is not two phase at the desired pressure,use an isothermal flash. Change the temperature until you get some separation in thedirection you do this list the components in increasing boiling point and determine keycomponents. Light key goes mostly to the top. Heavy key goes mostly to in next = DISTILLATION/ABSORPTION COLUMN DESIGNChE 4253 - DESIGN IChE 4253 - DESIGN IMULTICOMPONENT SYSTEMS : Use Pro IICase 2: You know nothing, not even the number of trays needed.

5 Replace the flash by a three plates COLUMN , with similar specs as those given by the flash outlet streams. It should not be a big problem to get Add the components that are missing. Do it slowly, increasing their concentration until you reach the desired values. 6. Keep tightening the specs and increasing the number of plates accordingly, so that you meet the separation you want.