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evoparation

evoparation

shivaram
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evoparation

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  1. EVAPORATION HEAT TRANSFER COEFFICIENTS AND SINGLE EFFECT EVAPORATORS By T.Shivakumar B.Pharmacy Shiva.pharmacist@gmail.com

  2. PROCESS DESCRIPTION • OBJECTIVES • CONCENTRATE SOLUTE • RECOVER SOLVENT • FORM CRYSTALS • MECHANISM • HEAT EXCHANGE WITH PHASE CHANGE • BATCH OR CONTINUOUS http://www.niroinc.com/html/evaporator/rising_film_evaporators.html

  3. DESIGN FACTORS • SOLUTION FLUID VISCOSITY • HEAT TRANSFER COEFFICIENTS • PRESSURE DROPS • SOLUTE SOLUBILITY • SUPERSATURATED CONDITION • MATERIALS (BIO-MATERIALS) MAY BE HEAT SENSITIVE • DEGRADATION TEMPERATURE • ELEVATED PRESSURE • BOILING POINT ELEVATION http://www.aai-csi.com/images/evaporator.jpg

  4. EVAPORATION DESIGN FACTORS • HIGH TEMPERATURE REACTIONS • FOAMING • SCALING AND CORROSION http://www.aquasant-mt.com/Foam.159.0.html?&L=1 http://www.champ-tech.com/images/products/pipe.jpg

  5. OTHER DESIGN FACTORS • SPECIFIC HEAT • HEAT OF CONCENTRATION • FREEZING POINT VS. CONCENTRATION • GAS LIBERATION • TOXICITY • EXPLOSION HAZARDS • NEED FOR STERILITY

  6. EVAPORATION COMPARED WITH DISTILLATION • SOLUTE IN EVAPORATION IS GENERALLY NON-VOLATILE, RELATIVE TO SOLVENT http://www.novasep.com/technologies/img/evaporation-graph2.gif http://www.schoolscience.co.uk/content/4/chemistry/petroleum/knowl/images/still.jpg

  7. EVAPORATION EQUIPMENT • SUMMARIZED IN FIGURE 8.2-1 http://www.niroinc.com/html/evaporator/esys.html

  8. EVAPORATION EQUIPMENT • FORCED CIRCULATION AND RECOMPRESSION UNITS http://www.niroinc.com/html/evaporator/esys.html

  9. EVAPORATOR EQUIPMENT • PLATE & FRAME - CRYSTALLIZERS http://www.niroinc.com/html/evaporator/esys.html

  10. OSLO TYPE CRYSTALLIZERS http://www.niroinc.com/html/evaporator/esys.html

  11. OTHER CRYSTALLIZERS http://www.niroinc.com/html/evaporator/esys.html

  12. THIN FILM EVAPORATORS • USED FOR VISCOUS AND THERMALLY SENSITIVE MEDIA http://www.artisanind.com/documents/pa_lecithin.pdf

  13. INTEGRATED PLANT http://www.niroinc.com/html/evaporator/flash-ppt/VMPfcopy1.html

  14. EVAPORATOR CONFIGURATION • SINGLE STAGE EVAPORATORS • HEAT TRANSFER

  15. MULTI-EFFECT EVAPORATORS • STEAM FROM ONE EFFECT IS THE HEAT SOURCE FOR THE SECOND EFFECT http://www.nukem.de/global/downloads/englisch/Evaporation.pdf

  16. MULTI-EFFECT COUNTERFLOW CONFIGURATION • FIGURE 8.2-3 FEED-FOREWARD • PRESSURE IS REDUCED IN EACH STAGE • FEED & STEAM ENTER THE SAME STAGE IN THE TRAIN • FIGURE 8.2-4 – FEED-BACKWARD • PRESSURE IS INCREASED IN EACH STAGE • FEED & STEAM ENTER FROM OPPOSITE ENDS OF THE TRAIN

  17. PARALLEL FEED • SOLAR EVAPORATION SYSTEM http://www.rio5.com/proceedings/Solar/da_Silva_et_al_201-206.pdf

  18. EVAPORATOR HEAT TRANSFER • OVERALL HEAT TRANSFER COEFFICIENTS – SEE TABLE 8.3-1 • NEED TO KNOW RANGE TO REVIEW QUOTED DESIGNS • NOTE THAT PLATE & FRAME CAN HAVE HIGHER COEFFICIENTS THAN SHELL & TUBE.

  19. CHANGE OF PHASE HEAT TRANSFER • SECTION 4.8 FOR SUMMARY OF MECHANISMS • FIGURE 4.8-1 • CONVECTION • NUCLEATE • TRANSITION • FILM http://www.scielo.br/img/revistas/jbsmse/v27n1/25372f10.gif

  20. HEAT TRANSFER COEFFICIENTS • BASED ON ΔT

  21. OTHER CORRELATIONS • FOR EACH CONFIGURATION • PERRY’S PAGE 5-22 • HANDBOOK • http://www.wlv.com/products/databook/ch5_3.pdf • CONVECTIVE BOILING IN COILED TUBES • http://www.graham-mfg.com/downloads/12.pdf • BASED ON SURFACE • http://www.energy.kth.se/index.asp?pnr=10&ID=125&lang=0

  22. SINGLE STAGE MODELS • MASS AND ENERGY BALANCES

  23. MASS & ENERGY BALANCES • COMPONENT MASS BALANCE • SYSTEM HEAT BALANCE

  24. OTHER DESIGN FACTORS • LOWER EVAPORATION PRESSURE • WILL INCREASE EFFECTIVE ΔT • LOWER EVAPORATOR AREA • INCREASED SOLVENT CONDENSER AREA • HIGHER VELOCITIES MIST ELIMINATION • BOILING POINT ELEVATION • REDUCES EFFECTIVE ΔT WITH INCREASING CONCENTRATION

  25. BOILING POINT ELEVATION • DÜRING’S RULE – SOLUTION BOILING POINT IS LINEARLY RELATED TO PURE WATER NBPt AT PSYS • FIGURE 8.4-2 http://www.nzifst.org.nz/unitoperations/unopsassets/fig8-3.gif

  26. ENTHALPY-CONCENTRATION • HEAT OF MIXING EFFECTS • NON-IDEAL Dharmendira Kumar, M.; Ashok Kumar, P.; Rajendran, M., Salt Effect on the Enthalpy of Mixing of 1,4-Dioxane + Acetic Acid at 303.15 K , J. Chem. Eng. Data; (Article); 2003; 48(6); 1422-1424.

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