METHOD OF TREATING WASTE WATER FROM ARSENIC Russian patent published in 2013 - IPC C02F1/62 C02F1/28 C01G28/02 B01J20/24 

FIELD: chemistry.

SUBSTANCE: invention can be used in industry when treating waste or natural water from arsenic. The method involves use of a composite sorbent which contains as the sorbing component iron hydroxide particles which are immobilised on organic fibres, bringing the sorbent into contact with water to form insoluble arsenic compounds and separating the treated water from solid treatment products. In the sorbent, iron hydroxide particles are immobilised by cellulose fibres during chemical deposition thereof in an aqueous dispersion of said fibres. Waste water is brought into contact with the sorbent by mixing to form a suspension of solid treatment products containing arsenic. The cellulose fibres contain, wt %: at least 94% fibres with length of not more than 1.23 mm and at least 54% fibres with length of not more than 0.63 mm. The sorbent has the following composition, pts.wt: cellulose fibres -100, iron hydroxide - 20-500. Water treatment is carried out at sorbent concentration of 40-300 mg/dm³. Separation of the treated water from solid treatment products is carried out by pressure flotation, wherein the flotation sludge or a portion thereof is fed into the water treatment process.

EFFECT: method increases efficiency of the water treatment process, simplifies the treatment technology, increases the degree of purification of water with different contamination levels at high volume rate of treatment.

5 cl, 3 ex