Since self-priming pump is designed to automatically remove air and gases from the suction line, it can start and run without the need for manual priming. It is used in places like irrigation systems, factories, and wastewater treatment facilities where the fluid being circulated may contain a significant amount of gas or air. Using a special impeller design that generates a vacuum in the suction line, the pump works by drawing fluid into the apparatus and expelling any air or gas that may be present. A small amount of liquid is contained in a priming chamber on the impeller, which helps prime the self-priming pump and create the first suction.