Patent ID: 7644909

Claim:
An aeration system for aeration and/or mixing of water, comprising: at least one aeration unit having a pump/propeller inside a feed pipe, with which propeller/pump the water is sucked into a feed pipe, and the feed pipe to which the water to be aerated is sucked from beneath; a nozzle ring in the aeration unit, and which feed pipe expands in an upper part of the aeration unit by forming a conical space that works as a nozzle, the nozzle ring having at least one nozzle opening defined therein, the nozzle ending in at least one annular nozzle opening; the aeration unit being placed in the water to a right depth in such a way that the water flow caused by a pump/propeller goes to one or more of the annular nozzle openings at or close to a surface of the water; and another smaller propeller being disposed in the upper part of the system, the other propeller being different handed compared to the propeller of the propeller pump.