METHOD AND PLANT FOR BIOLOGICAL WASTEWATER TREATMENT Russian patent published in 2017 - IPC C02F9/14 C02F3/30 C02F3/12 B01D21/02 

FIELD: technological processes.

SUBSTANCE: method comprises supplying wastewater to aerotank (2) of the corridor type and treating the water with activated sludge in at least one anaerobic (AN), anoxic (D), aerobic (N) and transition zones formed over the entire length of the aerotank (2), separating the activated sludge in the secondary sedimentation tank (3) and its recirculation. Treatment of water with activated sludge is carried out in successive first anoxic (D1), anaerobic (AN), transition anaerobic-aerobic (AN/N), the first aerobic (N1), the second anoxic (D2), transition anoxic-aerobic (D/N) and the second aerobic (N2) zones of the aerotank or in successive first anoxic (D1), anaerobic (AN), transition anaerobic-aerobic (AN/N), the first aerobic (N1), the second anoxic (D2) and the second aerobic (N2) zones of the aeration tank. The transition anaerobic-aerobic (AN/N) zone is converted to anaerobic operating mode by shutting off the air supply and turning on the mechanical stirring devices (4) or to the aerobic operating mode by turning on the air supply and turning off the mechanical stirring devices (4). The transition anoxic-aerobic (D/N) zone is converted to aerobic operating mode by turning off the mechanical agitators (4) and turning on the air supply, and to the anoxic operating mode by turning off the air supply and turning on the mechanical agitators (4). The plant for implementing the biological treatment method comprises a wastewater supply device (1), an aerotank (2) divided by longitudinal baffles into at least one anaerobic (AN), an anoxic (D), aerobic (N), and a transition zone including mechanical agitators (4) and aerators (5), as well as the secondary sedimentation tank (3).

EFFECT: reliable operation of aerotank-sedimentation tank biological treatment system, stability and effectiveness of biological wastewater treatment from organic substances, from nitrogen and phosphorus compounds.

15 cl, 5 dwg