Hatco, To provide the oxygen source for the biological reaction, a jet aeration manifold with multiple jet nozzle assemblies is connected to a pump and a blower. Each jet has a primary mixing nozzle and an outer secondary nozzle. The tank contents are re-circulated by the pump through the primary mixing nozzle. Low pressure air is mixed with the liquid in the outer secondary nozzle creating fine bubbles. By turning off the blower connected to the airline, Anoxic mixing can be achieved with the same equipment to promote biological nutrient removal. No separate mixer is needed.
Jets have high oxygen transfer and higher alpha values compared to other aeration devices. The design alpha for Hatco jet system is 0.9 with successful installations. Performance data has demonstrated alpha values above 1 in the use of some industrial wastewaters. Jet nozzle gassing rates can vary significantly without major changes in oxygen transfer efficiency. Jets also provide energy efficient off-bottom solids suspension.
Tank liquid is pumped through the liquid line and through the inner nozzle. High velocity is created by the inner nozzle forming a jet plume. Compressed air is forced through the air line into the air transfer duct and then the outer nozzle. The high velocity jet plume from the inner nozzle shears the air in the outer nozzle creating fine bubbles. These bubbles are carried by the jet plume into the tank liquid. As the jet plume disperses and velocity slows. The buoyant force of the bubble causes the bubbles to rise.