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Aerobic digestion

Windrow: long line of composting sludge and bulking agent

What is aerobic digestion?

Aerobic digestion is the degradation of the organic sludge solids in the presence of oxygen. The oxygen is introduced as fine bubbles of air into the reactor. The micro-organisms in the sludge convert the organic material to carbon dioxide and water, and the ammonia and amino species to nitrate.

Conventional activated sludge (CAS) process Source: Judd Water & Wastewater Consultants / YouTube

Explaining the conventional activated sludge (CAS) process

Aerobic digestion resembles the conventional activated sludge (CAS) process − a process explained in this video − but excludes a wastewater feed and employs longer solids retention times.

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