Page 154 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

140 Applied Process Design for Chemical and Petrochemical Plants

Flash Pressure, 2 psig
(Lower than either X or Y)

Pressure: X, psig
Pressure: Y, pslg Vapor

Condensate Flashing
From Various 3

Headers
Liquid

I IF

’--
I I
I

I I I
I
1
I
I
I
I

Figure 2-53. Typical steam condensate flashing operation.

psig. The calculated total equivalent length of pipe, ’7. Refer to Figure 2-54 and note that required receiver
valves, and fittings is 600 feet. pressure is not shown, so calculate “factor scale” by
Using the Sarco chart, Figure 2-54, determine the rec- previous formula:
ommended line size for the return line.
Data: h, = 441 Btu/lb at 450 psig
1. Upstream steam pressure = 450 psig h, = 302 Btu/lb at 90 psig
2. Condensate load = 9,425 Ibs/hr L, = 886 Btu/lb at 90 psig
-
3. Return line pressure = 90 psig V = 4.232 cu ft/lb at 90 psig
4. Use the Sarco recommendation of 5,000 ft/min
5. Load factor
36.2 (4.232) (441 - 302)
“factor scale” value = = 0.092
886 (441 - 180)

53
8. Ft/min/lOO#/hr = - 576
=
6. Receiver pressure = 90 psig 0.092