GRANULATED CALCIUM CARBONATE PRODUCTION PROCESS Russian patent published in 2007 - IPC C01F11/18 B01J2/06 

FIELD: inorganic compounds technologies.

SUBSTANCE: invention relates to production of granulated calcium carbonate with improved consumer's properties, which can be used not only as alkaline fertilizer and land-reclamation agent but also as starting material for a variety of industrial fields, in particular in glassmaking industry. Process comprises mixing conversion calcium carbonate containing no more that 16% water with binding agent in specified weight proportion, granulating resulting mixture at 40-100° C and drying it at temperature not higher than 150° C to achieve residual moisture 0.2-4%. Binding agent is selected from aqueous solutions of a series of substances: carboxymethylcellulose sodium salt, mixture of sodium or potassium polyphosphate with sodium and/or potassium carbonates, sodium or potassium liquid glass, and lignosulfonate. Calcium carbonate is mixed: with carboxymethylcellulose sodium salt at weight ratio (0.001-0.01):1; with additive consisting of sodium or potassium polyphosphate and sodium and/or potassium carbonates at weight ratio (0.04-0.1):1; with sodium or potassium liquid glass at weight ratio (0.05-0.15):1; and with lignosulfonate at weight ratio (0.05-0.15):1 (recalculated for dry material). Thus obtained granulated conversion calcium carbonate is characterized by required chemical and granulometric composition with granule strength at least 1.5 MPa at residual moisture up to 4%.

EFFECT: improved performance characteristics of product.

4 cl, 4 ex