A liquid ring vacuum pump is easy to operate and is used in several applications across various industries. A liquid band pump works with a sealant needed in its operation. This liquid could be water, essential oil or any other solvent which is definitely rotated by an impeller within the casing of the pump.
As the shaft turns, a liquid band is created by the centrifugal force produced by the rotating impeller. This force holds the liquid ring against the inner wall structure of the pumping chamber. Because the impeller is situated eccentric to the pumping chamber, the depth of entry of the blades into the liquid ring decreases and improves as the impeller rotates. This creates increasing cell volume on the inlet interface side, creating vacuum.
On the Liquid-Ring Vacuum Pump discharge port side, the impeller cell volume decreases as the blades move further into the liquid band. This increases the pressure until discharge occurs through the discharge interface.
A continuing flow of refreshing sealing liquid is supplied to the pump via the sealing-liquid inlet.
In the case of the two-stage liquid ring pump, the discharge from the first stage does not discharge to atmosphere. Instead, the 1st stage discharges through the manifold resulting in the second 
stage along with through a discharge slot located in the intermediate plate between the first- and second-stage impellers.
