PLANT FOR BIOLOGICAL CLEANING OF DOMESTIC WASTE WATER Russian patent published in 1999 - IPC

FIELD: biological cleaning of domestic waste water where it is impossible to connect to sewage system. SUBSTANCE: plant includes septic tank-settler, device for biological cleaning of clarified waste water in aeration charge of aerotank with attached microorganisms; it is provided with diaphragm aerators; plant includes also second settler with airlift device for directing the sediment to septic tank-settler. Diaphragm aerators are located directly under bulk porous profiled charge at specific surface of 280 to 400 sq.m/cu.m; they located at distance from charge not exceeding the amount of expansion of diaphragm. Device for introducing clarified water into aerotank is located above charge; ratio of heights of aerotank, upper and lower zones of change of direction of motion of flow and zone of charging are equal to 9.5-10.0:0.95:1.0:6.5-7.0:1.8-2.0, respectively. Plant is additionally provided with trickling biofilter having charge at specific gravity of 0.80 to 0.95 g/cn.m, water receiving device which is combined with chamber of submersible pump and water decontamination device mounted under pump. EFFECT: enhanced reliability and improved cleaning of water. 1 dwg