METHOD OF PURIFYING ACIDIC WASTE WATER FROM HEAVY METAL IONS Russian patent published in 2013 - IPC C02F1/62 C02F1/24 C02F1/54 C02F101/20 

FIELD: chemistry.

SUBSTANCE: invention can be used to purify acidic waste water from heavy metal ions. The method involves step-by-step treatment of water, at the first step with calcium hydroxide and at the second and third steps with sodium carbonate and sodium phosphate, respectively, to obtain at each step treatment products in form of partially soluble or insoluble metal compounds which are strongly sorbed on sorbent-collector-floatation agent particles, and then separating the treatment products by pressure floatation. The sorbent-collector-floatation agent used is fibrillated cellulose fibres which contain, with respect to weight thereof, at least 94% fibre with length of not more than 1.23 mm and at least 54% fibre with length of not more than 0.6 mm with water retention of the fibres of not more than 4 ml/g. The fibrillated cellulose fibres are fed into the water in amount of 100 pts.wt per 100-1200 pts.wt insoluble metal compounds.

EFFECT: invention enables continuous treatment of waste water with any concentration of metal ions with complete removal thereof, and also process and recycle particles of metal compounds.

4 cl, 1 dwg, 4 ex