One thousand kilograms per hour of a mixture containing equal parts by mass of ethanol and water is distilled. Product streams leave the top and the bottom of the distillation column. The flowrate of the bottom stream is measured and found to be 673 kg/h, and the overhead stream is analyzed and found to contain 96 wt% ethanol. Find the flowrates of all components in all streams.

We can solve for the flowrate of Foverhead,total = 1000 - 673 = 327

Streams\mass flow rate Total Ethanol Water
Feed 1000 Ffeed,ethanol
Ffeed,water
Overhead 327 Foverhead,ethanol
Foverhead,water
Bottoms 673 Fbottoms,ethanol
Fbottoms,water



We can't do any more mass balances at this point because mass balances only move us up and down within columns and we don't know any information in any of the other columns. Is there some information that we haven't used yet? There is, so we should decide which box we can fill in next in our table.

Click on the box you think we can do next...


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