Page 149 - Petroleum and Gas Field Processing

Gas production rate: 8.0 MMSCFD
Oil viscosity: 10 cP
Oil specific gravity: 0.87
Water specific gravity: 1.07
Gas specific gravity: 0.6
Gas compressibility: 0.88
Operating pressure: 500 psia

Operating temperature: 90 F
Oil retention time: 10 min
Water retention time: 10 min
c d : 0.64
Solution
Determine g and o :
2:7 0:6 500 3
g ¼ ¼ 1:674 lb=ft
550 0:88
o ¼ 0:87 62:4 ¼ 54:288 lb=ft 3

Use Eq. (22) with d m equal to 500 m to determine the minimum diameter for
water droplet settling:

6686Q o 2
2
o
D min ¼ 2 in:
ð
o
w Þd m
6686 6000 10 2
2
D min ¼ ¼ 8023:2 in:
0:2 500 2
2
D min ¼ 89:57 in:
Use Equation (23) with d m equal to 100 m to determine the minimum
diameter for gas capacity constraint:
1=2
TZ g C d
2
D min ¼ 5058Q g
P o g d m
1=2

550 0:88 1:674 0:64
2
D min ¼ 5058 8
500 52:614 100
¼ 835:86 in: 2
D min ¼ 28:911 in:
Therefore, the minimum allowable vessel diameter is taken as the larger of
the two calculated above; that is, 89.57 in.

Copyright 2003 by Marcel Dekker, Inc. All Rights Reserved.