EFFLUENT PURIFICATION METHOD Russian patent published in 1998 - IPC

FIELD: sewage purification facilities. SUBSTANCE: this relates to purification of urban sewage containing organic inclusions such as proteins, carbohydrates, fats, oils, petroleum products, synthetic surface-active agents, and mineral inclusions such as clay, sand, scale, soot, various salts. According to method, urban sewage at delivery to primary settling structures is subjected to slow and directed flocculating mixing with active silt taken in amount of 35-70 mg/l at velocity gradient of 60-90 c^-1 during 300-600 s. Application of aforesaid method allows for enhancing efficiency of settling by 15-20% with reduction of capital expenses for structures. EFFECT: higher efficiency.