PROCESS OF BIOCHEMICAL PURIFICATION OF SEWAGE Russian patent published in 1995 - IPC

FIELD: biotechnology of purification of sewage. SUBSTANCE: the process of biochemical purification of sewage employs a new effective non-toxic foam suppressor. The latter includes a waste product of polyether production. The waste product comprises (wt): 28-30 bentonite; 41-44 monosubstituted potassium phosphate; 27-30 a block copolymer of propylene and ethylene oxides having 11-13 wt oxyethyl groups. The amount of the foam suppressor varies from 5 to 150 ml/g of the water to be purified. The purification effect as measured by Chem PC varies from 80 to 85% EFFECT: improved suppression. 2 cl, 1 tbl