PLANT FOR BIOLOGICAL PURIFICATION AND REMOVAL OF NITROGEN AND PHOSPHORUS FROM WASTE WATER Russian patent published in 1997 - IPC

FIELD: waste water treatment. SUBSTANCE: biochemical purification of household waste water and close to it, in respect to composition, waste waters may be used in small inhabited localities, resorts, hospitals, and also in microbiological industry. Plant includes cylindrical-conical sand catcher with means for tangentially introducing initial drains, which is equipped with gauze with 2-6-mm gaps, valve with lifting lever, and discharge pipeline. Plant further has mixing chamber, biofilter unit, air tank-settler, circulation pump, and arrangement with denitrificator and filter. Mixing chamber is connected with pump suction line through siphon pipeline. Pump discharge line is connected with pipeline leading sludge mixture into distribution system of arrangement with denitrificator and filter. The latter communicates through pipeline with admission chamber of water-stream air ejection tube installed over contact tank. EFFECT: simplified operation due to using single pump.