The VPSA oxygen generation plant is characterized by its short operating cycle (generally only tens of seconds), so the exhaust pressure of blower will change rapidly with large fluctuation ranges during operation. Based on the principle of vacuum pressure swing adsorption, the blower is required to satisfy the stability of gas volume under the circumstance, which is the essential condition for stabilizing the gas flow rate in adsorption vessel and ensuring the service life of the adsorbent and the performance of VPSA oxygen production plant.

The Roots blower is a volumetric rotary blower that keeps the two rotors meshed by the synchronizing gears at the shaft end. The concave curved surface of the rotor and the inner wall of cylinder constitutes a working volume. The gas is taken in from the suction port during the rotation of rotor, when moving near and connecting with the exhaust port, the pressure in the working volume suddenly rises and the gas is delivered to the exhaust passage due to the returning of the higher-pressure gas. The two rotors do not touch each other, and the gaps between them are tightly controlled to achieve encapsulation so that the discharged gas is free from lubricating oil.

The most prominent feature is that when the pressure is adjusted within the allowable range, the flow rate changes little. The pressure selectivity is flexible, thus it can transmit gases compulsorily. It has the advantages of simple structure, easy maintenance and long service life.

In addition, it is suitable for gas delivery and pressurization in low-pressure conditions and can also be used as a vacuum pump. Therefore, the Roots blower is suitable for VPSA oxygen production plant, which is a common consensus in the development of VPSA oxygen generation technology over the years.