Jet aerators use the ejector method of contacting gases and liquids. The jet consists of a double nozzle arrangement. Each jet has a primary nozzle, an intermediate high shear mixing chamber, and an outer secondary nozzle.

Mixed liquor, recirculated from the tank, moves through the primary inner nozzle where it becomes a high velocity, low pressure stream.

Low pressure gas enters the mixing chamber perpendicularly to the high velocity liquid stream. Intense contacting and mixing of the two streams occurs in the high shear mixing chamber. The intimate contact between gas and liquid streams results in the formation of micron-size bubbles.

The fine bubble gas/liquid mist jets out through the secondary nozzle into the main tank volume. The high velocity plume from the secondary nozzle travels horizontally, spreading throughout the tank volume before riding to the surface.

The horizontal travel of the plume maintains high pressure conditions for a longer time than conventional diffused air systems. This high pressure condition gives the gas bubbles a greater opportunity to dissolve in the liquid, increasing the oxygen transfer efficiency.

Injection of the plume into the tank volume provides all the necessary mixing energy. The expanding plume’s powerful movement creates fine eddy currents in the surrounding liquid, thoroughly mixing the tank and keeping the MLSS solids in suspension.

High velocity gradients form within the tank volume and enhance mixing and solids suspension. The gradients are of a random nature, insuring the uniformity of the aerated liquid and the thorough suspension of solids.

When the initial horizontal momentum of the plume dissipates, it rises to the top of the liquid surface. This produces an air lift effect that further mixes the tank contents.

The jet plume also creates good molecular dispersion, sending oxygen molecules to microorganisms much faster. Such intimate mixing of reactants assures effective process operation.