What is the main purpose of aeration in wastewater treatment systems?

The main purpose of aeration in wastewater treatment systems is to increase the oxygen level for microbial activity. This process is vital because aerobic microorganisms require oxygen to thrive and break down organic matter in the wastewater. By injecting air into the treatment system, the dissolved oxygen levels are elevated, enabling these microorganisms to efficiently decompose pollutants. This biological treatment is essential for reducing biochemical oxygen demand (BOD), which is an indicator of the organic pollution levels in water.

Enhancing the oxygen supply not only supports the growth and activity of beneficial microbes but also improves the overall efficiency of the wastewater treatment process, leading to cleaner effluent being discharged into the environment. This function of aeration is fundamental in both activated sludge systems and other biological treatment methods where aerobic digestion plays a critical role.