MULTICOMPONENT DISTILLATION

SINGLE STAGE FLASHUSES TWO PHASE EQUILIBRIUMFLASHBUBBLE POINTDEW POINTCAN BE TWOLIQUID PHASESUSES RELATIVE VOLATILITY

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METHODS TO OBTAIN KiEMPIRICAL DATASET UP EXPERIMENTS TO MEASURE y = y(x,P,T)FIT TO STANDARD CORRELATIONS DATA CAN BE BASED ON BINARY SETS - SEE PERRY'S SECTION 13 FOR BINARY DATA GENERAL CORRELATIONS FOR SPECIFIC TYPES OF MIXTURES - UNIQUAC

METHODS TO OBTAIN KiDEPRIESTER CHARTS FOR HYDROCARBON SYSTEMSLOW TEMPERATURE DATAPERRYS FIGURE 13-14, P. 13-17

METHODS TO OBTAIN KiDEPRIESTER CHARTS FOR HYDROCARBON SYSTEMSHIGH TEMPERATURE DATAPERRYS FIGURE 13-14, P. 13-18

METHODS TO OBTAIN KiAIR SEPARATION PLANT DATAhttp://www.cryogenic-consulting.com/argon.pdf#search=%22AIR%20SEPARATION%20EQUILIBRIA%22

FLASH CALCULATIONSBUBBLE POINT PRESSURE (DIRECT)T AND xi ARE GIVEN, FIND yi AND P

BUBBLE POINT TEMPERATURE (T & E)P AND xi ARE GIVEN, FIND yi AND T

FLASH CALCULATIONSDEW POINT PRESSURE (DIRECT)T AND yi ARE GIVEN, FIND PSYS AND xi

DEW POINT TEMPERATURE ( T & E)P AND yi ARE GIVEN, FIND T AND xi

FLASH CALCULATIONSPARTIAL FLASH zi = 1P, T AND zi ARE GIVEN, FIND xi & yiFLASH LINES ARE DEVELOPED FOR EACH COMPONENT WITH A COMMON f

SOLVE BY T&E FOR VALUES OF V IN f = V/F

MULTICOMPONENT FRACTIONATIONGENERAL DESIGN CONSIDERATIONSSPECIFY PRESSUREDETERMINE NUMBER OF EQUILIBRIUM STAGESADJUST NUMBER OF STAGES FOR STAGE EFFICIENCYDESIGN TRAYSDESIGN COLUMNhttp://www.eia.doe.gov/kids/energyfacts/sources/non-renewable/images/FCCDistCol.jpg

SHORTCUT METHOD - PSEUDOBINARY SEPARATIONASSUMES TWO PRIMARY (KEY) COMPONENTS CAN BE USED TO MODEL THE PROCESSNON-KEYS ARE DISTRIBUTED BASED ON i,KEYKEY COMPONENTSDISTRIBUTED TO DISTILLATE & BOTTOMSMAJOR COMPONENTS IN FEEDNON-KEY COMPONENTSLIGHTER THAN LIGHT ARE ASSUMED TO GO TO DISTILLATEHEAVIER THAN HEAVY ARE ASSUMED TO GO TO BOTTOMSINTERMEDIATE ARE ASSUMED TO DISTRIBUTE TO DISTILLATE AND BOTTOMShttp://image.absoluteastronomy.com/images/encyclopediaimages/d/di/distillation_column.png

COMPONENT DISTRIBUTIONSEXAMPLE FROM AIR SEPARATIONKEYSO2N2NON-KEYArhttp://www.cryogenic-consulting.com/argon.pdf#search=%22AIR%20SEPARATION%20EQUILIBRIA%22

SHORTCUT METHODDISTRIBUTE KEYS BASED ON TARGET PRODUCT COMPOSITIONCOMPLETE DISTRIBUTION TO YIELD FEED AND PRODUCT MATRICESxFi, xDi, xBiCALCULATE NMIN WITH FENSKE EQUATION USING KEY VALUES

SHORTCUT METHODAVERAGE RELATIVE VOLATILITY, LK,HKFEED VALUE

TOP/BOTTOM AVERAGE

GEOMETRIC AVERAGESOVERALLTOP/BOTTOM

SHORTCUT METHODCHECK OF NON-KEY DISTRIBUTIONUSE FENSKE EQUATION RESOLVED FOR NON-KEY RELATIVE TO KEY:

SHORTCUT METHODMINIMUM REFLUX RATIOOPERATING LINES FOR EACH COMPONENT AT TOTAL REFLUXRECTIFICATION SECTION

STRIPPING SECTION

SHORTCUT METHODUNDERWOOD EQUATIONS COMPLETE BALANCE OVER THE COLUMN

NUMBER OF VALUES ARE (1 + NUMBER OF COMPONENTS BETWEEN KEYS)VALUE OF IS BETWEEN VALUES OF ij

SHORTCUT METHODUSE GILLILAND OR ERBAR-MADDOX CORRELATIONS TO DETERMINE N FOR A SPECIFIC RdMolokanov, International Chemical Engineering, 12(2), 209, 1972McCabe, Smith and Harriontt, Unit Operations of Chemical Engineering, Ed. 4, p, 578, 1985.

SHORTCUT METHODLOCATION OF FEED TRAYIS CRITICAL TO COLUMN EFFICIENCYLOSS OF SEPARATION INCOMPLETE SEPARATIONBASIS FOR ESTIMATE