A liquid band vacuum pump is simple to operate and is used in a number of applications across various industries. A liquid band pump works together with a sealant needed in its procedure. This liquid could be water, essential oil or any various other solvent which is 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 push holds the liquid ring against the inner wall structure of the pumping chamber. Because the impeller is located eccentric to the pumping chamber, the depth of access of the blades in to the liquid ring decreases and raises as the impeller rotates. This creates increasing cellular volume on the inlet interface side, creating vacuum.
On the discharge slot side, the impeller cell volume decreases as the blades move further into the liquid ring. This increases the pressure until discharge occurs through the discharge slot.
A continuing flow of refreshing sealing liquid comes to the pump via the sealing-liquid inlet.
In the case of the two-stage liquid band pump, the discharge from the first stage will not discharge to atmosphere. Instead, the first stage Liquid-Ring Vacuum Pump discharges through the manifold resulting in the second stage as well as through a discharge slot situated in the intermediate plate between the first- and second-stage impellers.