METHOD OF BIOLOGICAL PURIFICATION OF WASTE WATER Russian patent published in 2007 - IPC C02F3/30 

FIELD: biological purification of waste water.

SUBSTANCE: proposed method includes mechanical purification of waste water in first settler followed by delivery of waste water to bioactivator containing micro-flora where zones at heterogeneous content of oxygen in medium are maintained by controllable introduction of oxygen; then mixture of waste water with activated sludge is directed to secondary settler for separating the mixture into purified waste water and activated sludge which is continuously returned to the beginning of bioactivator. Sediment after first settler is recirculated to primary settler inlet for creating the hydrolysis process and heteroacetogenic process directly in primary settler. Zones of medium at heterogeneous content of oxygen are formed in secondary settler by regulating the rate of recirculation of activated sludge from secondary settler to bioactivator inlet. Zones of medium at heterogeneous content of oxygen in bioactivator are distributed horizontally.

EFFECT: reduction of volume of sediment and excessive activated sludge; low cost of maintenance of purification works; enhanced operational efficiency of purification works.

17 cl, 6 dwg, 3 tbl