Pressure Drop Across The Tower
Pressure Drop Across The Tower
(OP)
Hello All,
What do you expect the pressure drop across the tower reading if you have damage Trays (sieve/valve trays) ? HIGH OR LOW ?
Crude tower was opened for inspection and we found more than 10 valve trays are damaged !!!! we haven't seen any big changed on produtc quality (HGO).
What do you expect the pressure drop across the tower reading if you have damage Trays (sieve/valve trays) ? HIGH OR LOW ?
Crude tower was opened for inspection and we found more than 10 valve trays are damaged !!!! we haven't seen any big changed on produtc quality (HGO).





RE: Pressure Drop Across The Tower
Let's assume the dry tray pressure drop of one tray is 0.05 psi. Let's also assume your tray's weir is 3 inches, therefore the tray will be holding at least 3 inches of pure liquid. Assume HGO S.G. = 0.75. It takes 36.96" of HGO (S.G.=.75) to equal 1 psi. Therefore, 3"/36.96" = 0.08 psi. 0.05 + 0.08 psi = 0.13 psi/tray. 10 trays = 1.3 psi drop. This is an estimate of course, but hopefully it will give you something to go by.
RE: Pressure Drop Across The Tower
If for an operation standpoint there is no significant change in DP and little change in output then you probably best to leave it alone. However, if this is for knowledge prior to a turn around (planning scope and finding out you don't have to open that tower at all or ordering internals to decrease downtime) and you believe a tower may have damage or just may have history of damage as many do, you can have a TowerScan performed. This is done while the tower is operating and can provide alot of information on how the tower is operating and pin point any tray damage.
for more info:
http://www.towerscan.com/