The Sequencing Batch Reactor (SBR) is an activated sludge process designed to operate under sequences for the various phases of biological treatment where aeration and sludge settlement both occurring in the same tank. The SBR design is a fill and draw type activated sludge process where individual reactors are filled one by one in five discrete periods i.e. Anoxic fill, React, Settle, Decant and Idle / Waste sludge.

The SBR system can be designed with the ability to treat a wide range of influent volumes hence there is a degree of flexibility associated with working in a time rather than in a space sequence.

SBR aeration system generally consists of fine bubble air diffusers. In this process, the compressed air is sheared into small bubbles creating large specific surface area for higher mass transfer efficiency between air and wastewater. SBR produce sludge with good settling properties, provided the influent wastewater is admitted into the aeration in a controlled manner. An appropriately designed SBR process is a unique combination of equipment and software providing highest level of effluent quality on all parameters including BOD and Nutrient removal. Automated control minimizes the manual intervention and thus less possibilities of operational errors.