Page 328 - Process Equipment and Plant Design Principles and Practices by Subhabrata Ray Gargi Das

330 Chapter 11 Distillation

Vapour T ¼ 75 C; P ¼ 10 KPa

78 273 10 4 3 3
VBenzene ¼ 2:697 10 mt=m ¼ 0:2697 kg=m
r ¼ 3
22:4 10 ð273 þ 75Þ 101:3
92 273 10 4 3 3
r VToluene ¼ 3 ¼ 3:18 10 mt=m ¼ 0:3181 kg=m
22:4 10 ð273 þ 75Þ 101:3
106 273 10 4 3 3
Vo xylene ¼ 3:665 10 mt=m ¼ 0:3665 kg=m
r ¼ 3
22:4 10 ð273 þ 75Þ 101:3

Vapour stream (V) at T [ 75 C; P [ 10 kPa

3 3
Component mt mol/hr mt/hr m /hr r V mt/m
4 4
Benzene 9.352 10 0.0729 270.30 2.697 10
Toluene 6.346 10 4 0.0584 183.59 3.181 10 4
0-xylene 0.0158302 1.6782 4578.99 3.665 10 4
0.0174 1.8095 5032.88 3.595 10 4

4 3 3
r ¼ 3.595 x 10 mt=m ¼ 0.3595 kg=m
V
m V ¼ 1.8095 mt/hr ¼ 1809.5 kg/hr

Separator factor (s)
1=2
V L
s ¼ðm L =m V Þ ðr =r Þ
1=2
¼ 0:098
¼ð8748:5=1809:5Þ ð0:3595=879:8Þ
From Table 11.9 (system constant, SF, for vertical separator with demister pad @ 85% flooding),
ð0:1280 0:1310Þ
ð0:098 0:08Þ¼ 0:1283
SF V ¼ 0:1310 þ
0:02
1=2 1=2
l
r r v 879:8 0:3595
u v;max ¼ SF v ¼ 0:1283 m=sec ¼ 6:346 m=sec
v 0:3595
r
Inlet nozzle
m L þ m V ð8748:5 þ 1809:5Þ 3
mix ¼ ¼ 2:0935 kg=m
r ¼
L V 8748:5 1809:5
ðm L=r þ m V =r Þ
879:8 þ 0:3595