1 / 20

DISTILLATION DESIGN

STAGES VERSUS REFLUX. INCREASED REFLUXFEWER TRAYSLOWER INITIAL CAPITAL COSTHIGHER OPERATING COSTINCREASED NUMBER OF TRAYSLOWER REFLUXHIGHER INITIAL CAPITAL COSTLOWER OPERATING COST. EXAMPLE. START WITH EQUILIBRIUM DIAGRAMDEFINE OPERATING CONCENTRATIONSDETERMINE FEED CONDITIONSCALCULATE RdM

emlyn
Download Presentation

DISTILLATION DESIGN

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. DISTILLATION DESIGN

    2. STAGES VERSUS REFLUX INCREASED REFLUX FEWER TRAYS LOWER INITIAL CAPITAL COST HIGHER OPERATING COST INCREASED NUMBER OF TRAYS LOWER REFLUX HIGHER INITIAL CAPITAL COST LOWER OPERATING COST

    3. EXAMPLE START WITH EQUILIBRIUM DIAGRAM DEFINE OPERATING CONCENTRATIONS DETERMINE FEED CONDITIONS CALCULATE RdMIN SELECT RdDZN = 2 y0 = 0.3 LOCATE STRIPPING OPERATING LINE CALCULATE STAGES

    4. PROCESS IMPACTS REFLUX RdMIN REQUIRES INFINITE STAGES INCREASES REFLUX INCREASESS THE DRIVING FORCE REDUCES THE NUMBER OF STAGES NUMBER OF STAGES NMIN REQUIRES TOTAL REFLUX ADDING STAGES REDUCES NECESSARY DRIVING FORCE

    5. STAGE VS. REFLUX RELATIONSHIP RUNNING A SERIES OF CHECKS FOR NUMBER OF STAGES VS. REFLUX YIELDS ERBAR-MADDOX CHART GILLILAND CHART

    6. STAGE VS. REFLUX RELATIONSHIP CORRELATION FOR GILLILAND BY MOLOKANOV:

    7. COLUMN ENTHALPY BALANCES CONTROL VOLUMES FOR COLUMNS TOP OF COLUMN OVERALL CONDENSER SENSIBLE HEAT EFFECTS ARE A FACTOR

    8. COLUMN ENTHALPY BALANCES BOTTOM OF COLUMN OVERALL REBOILER OVERALL FOR COLUMN

    9. TRAY DESIGN FACTORS EFFICIENCY IS APPROACH TO EQUILIBRIUM OVERALL APPLIES FOR CONSTANT DRIVING FORCE MURPHREE BASED ON LOCAL DRIVING FORCES PROVIDES MORE ACCURATE STAGE COUNT LOCAL CONSIDERS VARIATIONS AT LOCATION ON TRAY

    10. APPLICATION OF ?M USING MURPHREE EFFICIENCY RESULTS IN AN EFFECTIVE EQUILIBRIUM LINE

    11. STAGES IN PACKED COLUMNS HETP = HEIGHT OF THEORETICAL PLATE TOTAL PACKED HEIGHT HETP DEPENDS ON TYPE OF PACKING HYDRODYNAMICS

    12. HETP DATA PACKING VENDORS PROVIDE DATA FOR ESTIMATES OF HETP VALUES ARE SPECIFIC TO MEASURED SYSTEMS CAN SHOW FLOODING LIMITS

    13. OTHER HETP VALUES HETP COMPARISON INDUSTRIAL COLUMNS 5 100 PLATES LARGE DIAMETERS CHROMATOGRAPHIC COLUMNS 1000 100,000 PLATES SMALL DIAMETERS AND CAN BE AFFECTED BY FLOW RATES

    14. HETP CORRELATIONS GENERAL CORRELATIONS FROM TEXT SECTION 11.5E:

    15. STABLE (EFFICIENT) OPERATION STABILITY EXISTS BETWEEN FLOODING AND WEEPING FLOODING IS THE UPPER LIMIT FOR FLUXES BASED ON EXCESS ?P NORMALLY GAS PHASE CONTROL ENTRAINMENT CAN LIMIT EFFICIENCY

    16. PACKED COLUMN STABLITY HETP VALUES CHANGE WITH HYDRODYNAMICS

    17. STABLE OPERATING RANGES CAN BE EXPRESSED IN TERMS OF ?P

    18. DESIGN FLUX FLOODING RESTRICTIONS FOR TRAY COLUMNS VALUES ARE BASED ON ENTRAINMENT OTHER LIMITS FROM WEEPING MUST BE DETERMINED THROUGH NORMAL OPERATION CAN USE RECYCLE TO RUN AT MINIMUM FLUX AT A PRICE. SIEVE TRAYS HAVE NARROW RANGE OF OPERATION CAP AND VALVE TRAYS CAN OPERATE AT LOWER TURNDOWN RATIOS VALVES HAVE LESS OPEN AREA WITH REDUCED GAS FLUX

    19. FOAMING IMPACTS FOAMING CAN ALSO IMPACT STABILITY DIFFICULT TO PREDICT A CHALLENGE TO ELIMINATE LESS OF A PROBLEM WITH PACKED BEDS

    20. MULTIPLE FEEDS/DRAW-OFFS INTERNAL COLUMN FLOWS CHANGE DUE TO - FEEDS DRAW-OFFS HEAT EXCHANGES

    21. MODIFIED McCABE DIAGRAM OPERATING LINES CHANGE FOR EACH SECTION

More Related