Aerobic Digestion

Aerobic digestion is a process in sewage treatment designed to reduce the volume of sewage sludge and make it stable, appropriate for subsequent use. It is a bacterial process occurring in the presence of oxygen. Bacteria rapidly consume organic matter and convert it into carbon dioxide, water and a range of lower molecular weight organic compounds.

Aerobic digestion is typically used in an activated sludge treatment plant. Waste activated sludge and primary sludge are combined and passed to a thickener where the solids content is increased.

This substantially reduces the volume that is required to be treated in the digester. The process is usually run as a batch process with more than one digester tank in operation at any one time. Air is pumped through the tank and the contents are stirred to keep the contents fully mixed. Carbon dioxide, waste air and small quantities of other gases including hydrogen sulfide are given off. These waste gases require treatment to reduce odors in works close to housing or capable of generating public nuisance. The digestion is continued until the percentage is degradable solids is reduced to between 20% and 10% depending on local conditions

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PROTEC is a privately owned company established in Doha, Qatar engaged in the fields of Engineering, Supply, Construction, Installation, Commissioning, Operation and Maintenance of various types of equipment for the Water, Waste Water, Energy, and Industrial markets.


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