METHOD OF CLEANING LOW-TURBID COLORED WATER Russian patent published in 1999 - IPC

FIELD: water treatment by coagulation; clarification of low-turbid colored water. SUBSTANCE: water is first subjected to pressure floatation for at least 15 minutes. Then water is kept in pressure reservoir at content in water-and-air mixture no less than 1.5% of volume of water to be treated for at least 10 minutes, after which mixture is introduced into water to be treated which contains coagulant; thickness of layer of water shall be no less than 1 m. EFFECT: reduced consumption of coagulant - aluminium sulfate by 3 to 5 times; reduced content of residual aluminium in cleaned water by 50%; reduced time required for coagulation. 2 tbl