Extended Aeration

It is an aerobic process for treating biodegradable wastewater to a high quality effluent and plants can be designed for simple operation and reduced attendance.

Screened wastewater is treated in an aeration tank designed to provide a retention time of between 24 and 30 hours. The process is continuous with incoming flow displacing an equivalent volume of mixed liquor from the tank. The aeration system is designed to be able to (1) satisfy the oxygen demand for the biological oxidation of the bCOD in the wastewater, (2) satisfy the oxygen demand due to endogenous respiration of the biomass, (3) meet the oxygen demand for biological nitrification, (4) provide adequate mixing within the reactor and (5) maintain a minimum dissolved oxygen concentration throughout the aeration tank.

The displaced mixed liquor passes through to a separate settlement tank where the biomass is settled out and returned to the aeration tank to provide the acclimatized activated sludge for continuing treatment. Clarified treated effluent is discharged to a watercourse (subject to approval from regulating authorities) re-used for another non-human consumption e.g. irrigation or recycle for toilet flushing after disinfection.

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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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