WASTE WATER TREATMENT APPARATUS Russian patent published in 2011 - IPC C02F3/22 

FIELD: chemistry.

SUBSTANCE: apparatus for biological treatment of waste water has a nitrifier-denitrifier aerotank (2) merged with a settling tank (4), having an anoxic zone and a nitrification zone, pipes for inlet and outlet of waste water, circulation and outlet of excess biomass, circulation of nitrate-containing waste water, air ducts and aerators (3), as well as air lifts for pumping returned active sludge (6) and intra-zone recirculation of biomass and nitrate-containing liquid (5). The apparatus is fitted with a split gas-collecting cap (7) lying in the nitrification zone below the level of the sludge mixture outside the perimetre of the settling tank (4) at a rising angle to the air lifts for intra-zone recirculation of biomass and nitrate-containing liquid (5), mounted at the point of intersection of the rising angles of the gas-collection cap.

EFFECT: high efficiency of treating waste water and high stability of operation of the system while lowering cost of treating waste water and environmental pollution at the same time.

2 cl, 4 dwg, 1 tbl