Patent ID: 6843470

Claim:
An air diffuser for use in a tank containing a mixed liquor, comprising: a diffuser tube immersed in the; a flushing pipe having an opening at its tip defining an outlet above the diffuser tube; and a flushing valve disposed in the flushing pipe, the diffuser tube having: a main pipe communicated at its basal end to an air supply source and communicated at its tip to the flushing pipe, the main pipe being located in a horizontal direction; and a plurality of blowholes provided at a lower part of the main pipe, characterized in that the flushing valve is opened while air is being supplied into the diffuser tube from the air supply source, the air supplied into the diffuser tube is evacuated through the flushing pipe, said mixed liquor inside the tank is refluxed into the diffuser tube through the blowholes following the evacuation of the air, and thus refluxed mixed liquor, together with the air forming a gas-liquid mixed phase flow, runs through the flushing pipe and evacuates therefrom, wherein the mixed liquor is refluxed intermittently into the diffuser tube while the flushing valve is open and air is supplied into the diffuser tube from the air supply source, said intermittent refluxing of the mixed liquor caused by variations in pressure inside the diffuser tube, thereby causing pulsation in the diffuser tube.