METHOD AND PLANT FOR AEROBIC BIOLOGICAL PURIFICATION OF WASTE WATER

FIELD: water purification. SUBSTANCE: invention deals with biological purification of waste water in purification installations of inhabited locations, agricultural, and industrial enterprises and consists in the following. Excess activated sludge is physico-mechanically treated to stimulate the process of production by microorganisms of extracellular biopolymers. A portion of treated activated sludge is mixed with initial waste water prior to its introducing into the primary settler, and the other portion is combined with a waste water-activated sludge mixture discharged from air tank prior to enter the secondary settler. Stirring the above suspensions is carried out under condition of maximally using bioflocculating capability of treated sludge mixture by way of choosing stirring regimes in respect to duration, intensity and character of interaction of coagulating agents with disperse solid and colloidal particles. Type and regimes of physico-chemical treatment of activated sludge are selected on condition of full exhaustion of cell protein reserves to ensure maximum concentration of extracellular biopolymers in medium under treatment. Purification plant is additionally provided with a device for physico-chemical treatment of excess activated sludge to intensify bioflocculation process and stirring means connected in parallel to this device to mix a portion of treated activated sludge with initial waste water prior to its entering primary settler and to mix another portion of treated activated sludge with a mixture of waste water and activated sludge withdrawn from air tank prior to its entering secondary settler. EFFECT: efficient system process proposed. Использование: биологическая очистка сточных вод в очистных сооружениях населенных пунктов, сельскохозяйственных и промышленных предприятий. Сущность изобретения: избыточный активный ил подвергают физико-механической обработке для стимулирования процесса выделения микроорганизмами внеклеточных биополимеров. Часть обработанного активного ила перемешивают с исходной сточной водой перед подачей ее в первичный отстойник, а другую часть - со смесью сточной воды и активного ила, отводимой из аэротенка, перед подачей ее во вторичный отстойник. Процессы перемешивания указанных суспензий ведут в условиях максимального использования биофлокулирующей способности обработанной иловой смеси путем подбора режимов перемешивания по времени, интенсивности и характеру взаимодействия коагулирующих агентов с дисперсными тв