Vacuum pump in oil refining and petrochemical production

Vacuum pump is a kind of conveying machinery that draws air from negative pressure and exhausts at atmospheric pressure. Its purpose is to create and maintain the vacuum required by the process system. The vacuum pumps commonly used in oil refining and petrochemical production include reciprocating vacuum pump, water ring vacuum pump and jet vacuum pump.

The structure and working principle of reciprocating vacuum pump are basically the same as that of reciprocating compressor. The pressure difference between inside and outside the cylinder is very small, but its compression ratio is very large (for example, for 95% vacuum degree, the compression ratio is about 20). Therefore, the suction and discharge valves of the reciprocating vacuum pump must be light and flexible, easy to open and close; the volume of the rest gaps must be very small. At the same time, in order to reduce the adverse effect of the residual gas in the clearance on the pumping rate of the vacuum pump, the inner wall of the two ends of the cylinder of the vacuum pump is often provided with a balance airway connecting the two sides of the piston.

At the end of exhaust, the balance port can make the clearance communicate with the other side of the piston for a short time, so that the residual gas in the clearance can flow to the other side of the piston through the balance airway, so as to reduce the pressure of the gas in the clearance, so as to improve the suction efficiency, that is, to increase the volume coefficient. The limit vacuum produced by reciprocating vacuum pump can reach about 2KPa (absolute pressure). The gas discharged by reciprocating vacuum pump should not contain liquid. If the gas contains a large amount of steam, the condensable gas must be removed (generally condensed) before entering the vacuum pump, that is, reciprocating vacuum pump belongs to dry vacuum pump.

Water Ring Vacuum Pump

Water Ring Vacuum Pump manufacturers

Oil Diffusion Vacuum Pump