A feed input stream (F) which consists of 35%EtOH and 65%water is channelled into a distillation column. At the lower end of the column, there is an output stream W which consists of 5%EtOH an d 95% water. At the upper end of the column, the stream is passed into a condenser where the distillate W comes out. W consists of 85%EtOH and 15%water.
How do you calculate the kg of D per kg of F and per kg ofW?
Can anyone pls help me. Thanks so much.
2007-01-26 16:51:09 · 1 answers · asked by sky_blue 1 in Science & Mathematics ➔ Engineering
Basis: 100 kg of Feed
F=Feed
D=Distillate
W=Bottoms
F=D+W Overall
.35F=.85D+.05W EtOH
.65F=.15D+.95W Water
For EtOH
.35(100kg)=.85D+.05W
35kg=.85D+.05W
For water
.65(100kg)=.15D+.95W
65kg=.15D+.95W
Linear system
35kg=.85D+.05W
65kg=.15D+.95W
Isolate D using the EtOH form
(35kg-.05W)/.85=D
Plug D into the water form
65kg=.15((35kg-.05W)/.85)+.95W
65kg=(5.25kg-.0075W)/.85+.95W
65kg=6.18kg-.0088W+.95W
65kg=6.18kg+.9412W
58.82kg=.9412W
W=62.49 solve for D using the overall form.
F=D+W
100kg=D+62.49kg
D=37.51kg
D/F=.375 kg of distillate per kg feed
D/W=.625 kg of distillate per kg of bottoms
And that is it.
2007-01-27 14:01:43 · answer #1 · answered by Scott S 4 · 0⤊ 0⤋