Activated sludge process modifications, like aerated lagoons and oxidation ditches are some of the mechanical aerator applications. There are a few requirements, which are more important for certain applications. Upon selecting the aerators based on the oxygen transfer, sludge suspension and it's associated blending requirements in the activated sludge process can be satisfied. Determination of aeration equipment size selection is possible with aerated lagoons sludge suspension and the associated blending. Mechanical aerator is motor driven and integrates liquid aeration and mixing. Some of such aerators create a gas - liquid interface by entraining air from the atmosphere and dispersing that air into bubbles. Other types of such aerator disperse liquid in droplets form and produce jets or thin films that contact the air in the atmosphere. Some other types can create both, air bubbles and liquid droplets.
The two major groups of this aerator, include:
Both groups can be further divided into submerged aerator and surface aerator.