Secondary clarifiers

Secondary clarifiers are typically implemented in various configurations (circular, longitudinal, or Dortmund-type), with an emphasis on uniform influent distribution, optimized retention time, and efficient sludge removal.

The objective of the process is efficient sludge separation, return of activated sludge to the biological process (RAS), and removal of excess sludge (WAS) from the system. At the same time, scum is removed from the surface, and treated water is evenly collected via outlet weirs or submerged perforated pipes. The tank design and equipment are developed with a focus on stable hydraulic conditions, minimization of short-circuiting, and gentle handling of activated sludge.