PROCESS OF PRODUCING CALCIUM CARBONATE FROM LIME PRODUCTION EMISSION GASES Russian patent published in 2006 - IPC C01F11/18 C04B2/10 C01B31/24 

FIELD: inorganic products production.

SUBSTANCE: invention is designed for use in production of pure and fine calcium carbonate from emission gases and comprises firing of limestone producing calcium oxide and emission gases. Thus obtained calcium oxide is treated with water to form calcium hydroxide, which is supplied to carbon dioxide-containing gas treatment process until concentration of calcium carbonate in solution achieves 60-250 g/dm³. Resulting calcium carbonate suspension is filtered and dried. Emission gases from limestone firing stage are first treated with water to achieve solids-to-liquids ratio 1:(4÷20). Resulting mixture of calcium hydroxide with impurities is separated from carbon dioxide-containing gases and discharged. Prior to be filtered, calcium carbonate suspension can be concentrated by decantation for 0.5-1.0 h.

EFFECT: increased purity of calcium carbonate and reduced production cost.

2 cl, 1 dwg