Title Mass Transfer Part (9) 1.4 MB 36
```                            Mole fraction of acetic acid in
Vapour, y
```
##### Document Text Contents
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Determine the number of plates to be provided and the correct location of the feed

plate.

Equilibrium data:

18) A continuous fractionating column, operating at atmospheric pressure, is to

separate a mixture containing 30-mole % CS2 and 70-mole % CCl4 into an

overhead product of 95-mole % CS2 and a bottom product of 95-mole % CCl4.

The feed enters the column as liquid at its boiling point.

Assuming an overall plate efficiency of 70% and a reflux ratio of 3.16, determine

the number of plates to be provided.

Mole fractions of CS2 in liquid (x) in equilibrium with mole fraction CS2 in

vapour (y) are as under:

Equilibrium data:

19) A feed containing 50 mole% Heptane and 50 mole% octane is fed into a pipe still

through a pressure reducing value and then into a flash discharging chamber. The

vapor and liquid leaving the chamber are assumed to be in equilibrium. If the

fraction of feed converted to vapor is 0.5, find the composition of the top and

bottom plates. The following table gives VLE data;

x, mole fraction of heptane in

vapour phase

1.0 0.69 0.4 0.192 0.04

5

0.0

y, mole fraction of heptane in 1.0 0.93 0.7 0.538 0.17 0.0

x 0.029

6

0.0615 0.258 0.390 0.532 0.663 0.75

8

0.860

y 0.082

3

0.1555 0.495 0.634 0.747 0.830 0.88

0

0.932

x 2.9

6

11.06 25.8 53.18 66.3 75.75 86.04

y 8.2

3

26.6 49.5 74.7 83.0 88.0 93.2

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