A Liquid-Ring Vacuum Pump china liquid band vacuum pump is easy to operate and can be used in several applications across various industries. A liquid band pump works with a sealant needed in its procedure. This liquid could be water, essential oil or any additional solvent which can be 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 of the pumping chamber. Since the impeller is situated eccentric to the pumping chamber, the depth of access of the blades into the liquid ring decreases and increases as the impeller rotates. This creates increasing cellular volume on the inlet interface side, creating vacuum.
On the discharge port side, the impeller cell volume decreases as the blades move further in to the liquid band. This increases the pressure until discharge takes place through the discharge port.
A continuing flow of clean sealing liquid comes to the pump via the sealing-liquid inlet.
Regarding the two-stage liquid band pump, the discharge from the 1st stage does not discharge to atmosphere. Rather, the first stage discharges through the manifold resulting 
in the second stage and also through a discharge interface positioned in the intermediate plate between your first- and second-stage impellers.