METHOD OF REMOVING HEAVY METALS FROM WASTE WATERS FROM SOLID DOMESTIC WASTE DUMPS Russian patent published in 2001 - IPC

FIELD: waste water treatment. SUBSTANCE: method is realized by treating waste waters and recycling them through bulk of waste. For treatment, waste water is mixed with lime milk to pH 9.0-9.5. Treated waste water is then spread throughout the surface of dump with velocity 1-2 mm a day. Total amount of recycled treated waste water should not exceed 200-300 mm a year. Treatment is continued until achieving neutral reaction of waste water passed through drainage system. In case when filtrate has alkali reaction and concentration of heavy metals therein exceeds maximum permissible value, recycling of treated filtrate is continued to maximum reduction of heavy metal concentration. Process can be performed predominantly during warm period (spring, summer, autumn) at air temperature not below 0ю . Particularly important is using proposed method in yearly period of dump life. EFFECT: speeded up biological purification of waste water, increased degree of purification, and enabled process control. 2 cl