Can a screw pump be used as a heavy oil unloading pump?
Thread Content
This is a twin-screw pump, which was originally used as a pump for transferring heavy oil between tanks. Now, it is intended to install a backflow device at the inlet of this screw pump, with a pipe diameter that matches that of the oil discharge pipeline. Connect directly to the tank truck’s oil discharge port. Is this okay? I know that centrifugal pumps can be used to discharge oil in this way; my previous company did use them for this purpose, and the results were good, but those pumps were used for discharging light oil. I want to discharge the heavy oil now, but I’m not sure whether a negative pressure can be created at the inlet of the screw pump to draw the oil out of the tank truck. Or could we add nitrogen through the opening on top of the tank truck? Would that work? The ultimate goal is to avoid having to install an additional dedicated screw oil unloading pump, thereby saving money
Refer to http://bbs.hcbbs.com/thread-1278477-1-1.html
Screw pumps are excellent for transporting materials with high viscosity
Screw pumps have self-priming capability and can be used
Absolutely. Not to mention heavy oil, even asphalt will do. As long as the NPSHa is not too low, that’s fine. You can ask the screw pump manufacturer what the NPSHr is. The viscosity of heavy oil generally does not exceed 1500, and the height of the unloading hose on trains usually does not exceed 4 meters (the length doesn’t matter); this twin-screw pump can basically meet these requirements. If considering suction height issues, the diameter of the flexible hose should be as large as possible.