Long Aerated Activated Sludge System is an important technology used in water treatment systems with the Turkish abbreviation "UHAÇ (Uzun Havalandırmalı Aktif Çamur Sistemi)". In this process, purely biological wastewater treatment is carried out with activated sludge.
This system is a purification method in which organic pollution is removed with the help of suspended microorganisms. The process consists of aeration tank, settling tank and sludge return system. Before aeration, floating and self-precipitating substances must be removed by pre-treatment. Activated sludge systems can be operated effectively with suitable reactor configurations for carbonaceous organic matter removal, nitrification, denitrification, excess biological phosphorus removal.
In activated sludge ponds, which can be designed as a full-mixed or piston-flow reactor, the wastewater first passes through the aeration pond and then is directed to the final settling pond.
In the final settling tanks, the treated water is separated from the biomass by the effect of gravity and transferred to the next treatment units such as disinfection and filtration, or discharged.