METHOD OF TREATING WASTE WATERS Russian patent published in 1997 - IPC

FIELD: waste water treatment. SUBSTANCE: invention concerns waste waters containing organic, mainly protein impurities, in particular, waste water from potato-starch production. After potato starch is produced, drain water system contains cell juice and washing water which is submitted to additional treatment. The latter consists in mixing washing water with liquid part of cell juice followed by separating coagulate and anode oxidation with subsequently restoring pH value of liquid fraction of mixture in cathode chamber of diaphragm electrolyzer. Such treatment leads to chemical and biochemical oxygen demand values suitable for permissible concentrations of impurities and excludes bacterial contamination which make possible reutilization of treated water or draining it into sewage systems or into open reservoirs. At the same time, additional amount of protein product useful in food industry is produced. EFFECT: increased purification degree and protein product recovered.