extended-aeration method

sanitation engineering

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June 26, 2026

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The extended-aeration method is a variation of the activated-sludge process used in wastewater treatment. This method omits the primary settling step and is efficient for treating smaller sewage flows, often found in places like motels or schools. These systems are typically housed in prefabricated steel tanks known as package plants. The process involves aerating the wastewater, allowing microorganisms to consume organic impurities. Extended aeration systems are designed to provide a sufficient amount of aeration time to effectively treat the sewage, reducing the biochemical oxygen demand (BOD) before the treated water is discharged.1

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wastewater treatment
Activated sludge
Extended aeration and contact stabilization systems omit the primary settling step. They are efficient for treating small sewage flows from motels, schools, and other relatively isolated wastewater sources. Both of these treatments are usually provided in prefabricated steel tanks called package plants. Oxygen aeration systems…
Read More
Extended aeration and contact stabilization systems omit the primary settling step. They are efficient for treating small sewage flows from motels, schools, and other relatively isolated wastewater sources. Both of these treatments are usually provided in prefabricated steel tanks called package plants. Oxygen aeration systems…
Read More