Answers to Selected Odd-Numbered Exercises
in
“Separation Process Principles” by
J. D. Seader and Ernest J. Henley
Chapter 9
9.1 Total condenser
30 psia
9.3 Column D-1: partial condenser, 35 psia Column D-2: total condenser, 20 psia
9.5 (a) 7.4
(b) 5.4 (c) 2.2
9.7 8.4
Distribution:
kmol/h:
Component Distillate Bottoms
C3 2499.996 0.0042
iC4 399.63 0.37
nC4 594 6
iC5 15 85
nC5 6.12 193.88
nC6 0.001 39.999
nC7 8x10-7 50
9.9
% recovery of C3 Distillate rate, lbmol/h
99.5 230 97.5 226 90.0 210 75.0 180 50.0 130 25.0 80 10.0 50 2.5 35
9.11 294 kmol/h
Distribution:
kmol/h:
Component Distillate Bottoms
C3 2500 0
iC4 400 0
nC4 594 6
iC5 15 85
nC5 18 182
nC6 0 40
nC7 0 50
nC8 0 40
9.13 17.8
9.15 Action is more important in the stripping section.
Gilliland correlation is empirical based on the rectification section. A correlation based on the stripping section would be more accurate.
9.17 (a) 5.9
(b) Distribution lbmol/h:
Component Distillate Bottoms
C3 5.00 0
iC4 14.76 0.24
nC4 23.13 1.87
iC5 3.60 16.40
nC5 2.53 32.47
(c) Only non-key distributing is nC5, with 2.88 lbmol/h to distillate.
44.6 lbmol/h of minimum reflux
9.23 % absorption
Component (a) N = 4 (b) N = 10 (c) N = 30
C1 0.014 0.014 0.014
C2 0.071 0.071 0.071
C3 0.021 0.21 0.21
nC4 0.63 0.73 0.74
9.27 Distribution:
lbmol/h:
Component Bottoms Vapor out
C1 0.0 59.5
C2 0.0 73.6
C3 0.2 153.0
nC4 32.8 140.7
nC5 37.8 20.4
