METHOD AND PLANT FOR BIOLOGICALLY TREATING WASTE WATERS Russian patent published in 1998 - IPC

FIELD: waste water treatment. SUBSTANCE: invention relates to waste waters originating from chemical plants, food and processing enterprises. Waste water treated in air tanks flows down from 20-30-cm height into slot well of purification tank filled with manna and then passes through cellular barrier and through inert material. Coarse inert material layer 15-20 cm thick and overlaying fine inert material layer are disposed near the bottom of purification tank 1.2-1.3 m deep, dimensions of layers being 1.5 m in width and at least 2 m in length. Waste water ascends through slot well to triangular overflow and flows down onto a tray, spreads there, and falls 20 cm downwards into slot well of the second tank filled with reed. Process is repeated successively in tanks filled with calamus, fleur-de-lis, and reedmace, whereupon waste water drops into dissipating basin. Tanks are arranged in cascade and interconnected through common cellular walls. Vegetation period terminated, floriferous shoots with seeds are cut off the plants and put onto the surface of tanks. System is washed away with water and insulated from negative temperatures by hothouse structure. EFFECT: improved environmental quality of treatment. 5 cl, 3 dwg