Patent ID: 7533874

Claim:
A nozzle unit for the distribution of a gas into a liquid under pressurized conditions comprising two or more annular nozzles arranged within a pipe one after the other in the direction of flow, the two or more annular nozzles being angled to provide a restriction passage in the direction of the flow, each of the two or more annular nozzles overlapping another one of the two or more annular nozzles and each of the two or more annular nozzles having one or more apertures substantially perpendicular to the direction of flow for the supply of pressurized gas at the overlap, each aperture formed between the bottom surface of the overlapping annular nozzle and the top surface of the following annular nozzle as a passageway for transporting gas to the liquid flow, wherein the backside of the two or more annular nozzles and the inside of the pipe form an annular space for the supply of gas which is open toward the apertures.