METHOD FOR WASTEWATER PURIFICATION FROM HEAVY METAL IONS Russian patent published in 2023 - IPC C02F1/62 C02F1/66 

FIELD: treatment of industrial wastewater.

SUBSTANCE: method includes treatment of wastewater with milk of lime containing limestone and quicklime. The content of limestone and quicklime in lime milk is 3.3 % by weight at a ratio of limestone: quicklime equal to 1:10. At the stage of slaking lime and making milk of lime, carbon dioxide is introduced into the container with liquid using a forced flow of external atmospheric air in the form of a background impurity in an amount that is excessive for the formation of insoluble metal salts, namely their basic carbonates. Then the flow is sent to settling ponds for clarification. In settling ponds, water is acidified to a pH value of 8 due to the natural absorption of carbon dioxide from the atmosphere through the open surface of the ponds. Then the purified water is removed. As an additional source of carbon dioxide in the injected air flow, carbon dioxide-containing combustion products of carbon-containing fuel are used.

EFFECT: creation of an industrially acceptable method of wastewater treatment at flowrates of tens and hundreds of cubic meters per hour.

3 cl, 1 dwg, 1 ex