An extended Aeration Sewage Treatment Plant (STP) is a type of Packaged Treatment Plant that uses the extended aeration process to treat wastewater. This process involves introducing air into the wastewater to promote the growth of aerobic bacteria that break down the organic matter. The treated water can then be reused for irrigation, flushing, or discharged safely into the environment.
The Extended Aeration STP is suitable for small to medium-scale wastewater treatment requirements, such as residential complexes, offices, hotels, and hospitals. It is designed to handle a wide range of influent wastewater quality and flow rates. The plant is pre-engineered, prefabricated, and compact, making it easy to install, operate and maintain.
The plant typically includes a collection tank, screen chamber, aeration tank, clarifier, and disinfection unit. In the collection tank, large solids and debris are removed by mechanical screens. The screened wastewater is then pumped into the aeration tank, where aerobic bacteria break down the organic matter. The treated water is then sent to the clarifier where any remaining solids settle at the bottom and the clear water is decanted over a weir. The final effluent is disinfected with chlorine or UV treatment before being discharged or reused.
Extended Aeration STPs have low operational and maintenance costs, are energy-efficient, and are easy to operate. They are environmentally friendly, and the treated water can be safely reused for non-potable purposes. The plant is designed to meet the stringent discharge norms set by regulatory authorities.