Centrifugal liquid pump with internal gas injection

Abstract

The centrifugal liquid pump is of the rotary discs types and has an integrated gas injector of very single yet efficient structure. This pump has a casing defining an inner, substantially cylindrical chamber with an axial liquid inlet and a tangential liquid outlet. A rotary impeller is rotatably mounted within the chamber. This impeller has first and second spaced apart discs which are rigidly interconnected at such a distance away from each other as to extend close to the opposite walls of the chamber. The first disc that extends close to the wall into which the liquid inlet opens has a central opening of the same diameter as the liquid inlet to allow the liquid injected through the inlet to enter within the chamber in between the discs. The second disc has a plurality of spaced apart openings located at a constant radius, which is inferior to the radius of the discs. A coaxial power shaft is connected to the impeller so as to rotate it in a given direction. This shaft extends out of the chamber in a direction opposite to the liquid inlet. A gas feed pipe is in open communication with the chamber. This gas feed pipe is connected to a hole made in the casing. This hole is located in the second opposite wall of the chamber at a radial distance substantially equal to the above mentioned constant radius. In use, the pressurized gas fed through the hole made in second opposite wall of the casing passes through the openings made in the second disc and enters into the chamber. The gas is then disolved in the liquid while the same moves between the discs toward the outlet of the pump.