Sizing a centrifugal pump in an oil storage tank battery
Sizing a centrifugal pump in an oil storage tank battery
(OP)
I enjoyed soaking up some knowledge from the pump calculation thread. I have a question sizing a centrifugal pump in an oil storage tank battery. I have a 400 barrel tank, they say it is (low Pressure/Atmospheric) It has a thief hatch on top to allow inbreathing and out breathing for thermal expansion of the liquid. My question is, since the tank has ounces of pressure on the tank, and is tied into a flare line, when sizing the pump (NPSH) can I use my liquid head and add the atmospheric pressure to the calculation, or since it is under a small amount of pressure I cannot use the atmospheric pressure.





RE: Sizing a centrifugal pump in an oil storage tank battery
Johnny Pellin
RE: Sizing a centrifugal pump in an oil storage tank battery
RE: Sizing a centrifugal pump in an oil storage tank battery
Johnny Pellin
RE: Sizing a centrifugal pump in an oil storage tank battery
RE: Sizing a centrifugal pump in an oil storage tank battery
RE: Sizing a centrifugal pump in an oil storage tank battery
RE: Sizing a centrifugal pump in an oil storage tank battery
Johnny Pellin
RE: Sizing a centrifugal pump in an oil storage tank battery
Start with atmospheric pressure at your elevation, add static head difference between low level in the tank to centerline of your pump (positive if the liquid is higher than your pump inlet), then subtract frictional losses from tank to pump and subtract liquid vapour pressure. If this is less than your 9ft then you're in trouble
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Sizing a centrifugal pump in an oil storage tank battery
There is 4-6 ounces of pressure in the vessel to keep the light ends from flashing to gas.
RE: Sizing a centrifugal pump in an oil storage tank battery
RE: Sizing a centrifugal pump in an oil storage tank battery
As JJpellin says, you need a margin over NPSH to avoid cavitation. 1-2 m is common.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.