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marchese85
11-04-2010, 09:38 PM
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aseptman
11-12-2010, 08:33 AM
Kettle Reboiler for Batch Distillation:
The TEMA type is say: AEU or simple vessel with U bundle
The Duty of Kettle is to generate required Boilup.
So your boil up is the max one in the batch operational sequence.

Your prob thus is :
Heating media: Steam at 2 bar(g) say 120 deg C
Process Fluid temp: This changes throughout the batch take the worst case that is last operation temperature
Heat Duty: To vaporise a pool of liquid at some rate say 2000 kg/hr This also then decides the Heat duty in Kcal/hr

Now the heat duty you say is only 25000 looks very small . Is it a small dia column because for water it means 25000/550= 50 kg vaporization? for organics it means about 250 kg/hr vaporization

As far as ur question goes
ur critical flux is: 345500 Kca/hr/m2
Duty is: 25000 Kcal/hr
for flux to be over than 345500 your area is a fraction?
also the U value for steam and org liq or even aq solutions shall be about 350-500 W/m2C
Thus use less U value and get higher area so that flux cal is lower than critical one
may be use hot water at 90 deg C?