METHOD FOR PURIFICATION OF FLOTATION RECYCLED WATER WITH REDUCTION OF CONTENT OF SILICON AND CALCIUM IONS IN IT Russian patent published in 2024 - IPC C02F1/463 C02F1/60 C02F9/00 

FIELD: various technological processes.

SUBSTANCE: invention relates to processing of mineral raw materials, in particular, to purification of industrial recycled water, which has passed the stage of flotation, with complete or partial circulation of process water. Method involves preparation of water for electrocoagulation and subsequent electrocoagulation of water with iron electrodes. When preparing water for electrocoagulation, first, the pH of the treated water is set to the pH range of 7–8 by feeding gaseous carbon dioxide into the treated water with control of the pH value. Further, an aqueous solution of calcium chloride is added to the treated water based on the specific consumption of calcium chloride of 0.5 g per litre. Prepared water is electrocoagulated for 8–10 minutes at DC density equal to 55–56 A per square meter of electrode area. After electrocoagulation of the prepared water, its clarification is performed.

EFFECT: reducing the content of silicon ions and calcium ions in water to a concentration of silicon of not more than 65 mg/l and calcium of not more than 25 mg/l, which enables to further use this purified water in industry, that is, reuse of process water with complete circulation, and also reduces hazard class of discharges.

1 cl, 8 tbl