Bioreactor for treating wastewater

Abstract

A bioreactor that has an internal sludge return function for treating wastewater is provided. Said bioreactor comprises a mixing zone (18), a static zone (28), and a mixed liquor circulation channel (26). The internal sludge return is accomplished by the integration of said static zone (28) that settles sludge, and said mixed liquor circulation channel (26) that provides a circulating stream of the mixed liquor for carrying settled sludge back to the mixing zone (18). Therefore, the microorganism concentration in the bioreactor of this invention is increased compared with conventional suspended-growth bioreactors, resulting in the improved wastewater treatment performance, reduced bioreactor size, simplified operation, reduced clarifier size, etc. The bioreactor of this invention can be operation in aerobic, anoxic, and anaerobic conditions to serve various wastewater treatment purposes.

Dependencies are inferred from the claim text.