METHOD OF GRANULATED PLASTER OBTAINMENT Russian patent published in 2009 - IPC C04B11/06 C01F11/46 

FIELD: construction.

SUBSTANCE: method of granulated plaster obtainment out of sour waste of hydrofluoride production involves waste neutralisation by lime-containing agent, performed simultaneously with granulation. Lime-containing agent is added in amount required by stoichiometric ratio or exceeding stoichiometric amount not more than by 5.0 wt %, and water is supplied at the same time in amount of 13.0-15.0 wt % of granulated product weight. The process is implemented in granulating drum at 10-20 rpm drum rotation rate for one hour to obtain at least 90-95% of granules of 20-50 mm size and the rest of 5-20 mm granules, with unbound sulfuric acid content of 0.02-0.05 wt %.

EFFECT: improved method of granulated plaster obtainment.

1 tbl