Abstract: A helical impeller liquid ring compressor includes a compressor body cooperating with first and second cover plates to define a compression chamber for receiving a helical impeller and a liquid. The compressor body has a compression section. The first cover plate seals a suction end of the compression chamber, and has an air inlet in fluid communication with the compression chamber. The second cover plate seals a pressure end of the compression chamber, and has an air outlet in fluid communication with the compression chamber. The impeller extends through the compression chamber, and includes a shaft rod and at least one helical blade. Upon rotation of the impeller, a liquid ring is generated from the liquid, and cooperates with the shaft rod and the blade to form air chambers.