What is the function of a diffuser in an aeration basin?

• A. To measure pH
• B. To heat the wastewater
• C. To deliver air and distribute oxygen to wastewater for microbial treatment.
• D. To remove solids

Answer: (C)

In an aeration basin, the diffuser’s job is to deliver air into the wastewater and distribute oxygen to support microbial treatment. Air is pumped through a diffuser grid, forming bubbles that transfer oxygen from the air into the water. This keeps dissolved oxygen at levels that enable aerobic bacteria to break down organic matter, speeding up the treatment process. The bubbling also helps mix the wastewater so solids stay in suspension and come into contact with the microbes. It doesn’t measure pH, heat the water, or remove solids.