BIOREACTOR FOR WASTEWATER TREATMENT Russian patent published in 2024 - IPC C02F3/22 C02F3/30 

FIELD: biological treatment of urban and similar industrial wastewater.

SUBSTANCE: invention is intended for biological treatment with activated sludge in anoxic and aerobic conditions with the implementation of nitrification and denitrification processes. The bioreactor comprises a container in which an aerobic nitrification zone and an anoxic denitrification zone are located, at least one airlift, at least one aeration system, and at least one pipeline for supplying initial wastewater. The bioreactor comprises at least one pipeline for entering return activated sludge into the tank and a pipeline for removing the sludge mixture from the tank into the secondary settling tank. The aerobic zone, with a dissolved oxygen concentration of 1.5-4 mg/l, is located in the upper part of the container, which has vertical walls. The anoxic zone, with a concentration of dissolved oxygen not exceeding 0.5 mg/l, is located in at least one lower part of the container, which has one section, the walls of which are inclined at an angle α =30-60°, or two, upper and lower, sections, whereas the walls of the upper section are made vertical, and the walls of the lower section are inclined at an angle α =30-60°. The aeration system is located on the border of the aerobic and anoxic zones and is fixed to the container. The aerated area is 30-60% of the cross-sectional area of the aerobic zone. The airlift is fixed to the walls of the container, one end rises above the container, and the other end is lowered into the anoxic zone at a distance of 0.15-0.25 m from the bottom of the container. The air supply to the airlift is carried out 0.25-0.4 m above the aeration system. Pipelines for supplying source wastewater and return activated sludge are fixed on the walls of the container and immersed at one end into the container below the aeration system at a distance that is 0.2-0.5 the depth of the anoxic zone.

EFFECT: bioreactor for wastewater treatment with biological nitrogen removal at a BOD_total:N ratio ≈ 4-20 by creating hydraulic conditions for the circulation of the sludge mixture in the bioreactor between the nitrification and denitrification zones, preventing the formation of bottom sediments using an airlift system without the use of circulation pumps and paddle mixers.

11 cl, 8 dwg, 1 tbl, 7 ex