CALCIUM SULPHATE-BASED COMPOSITIONS AND METHODS OF MAKING SAME

摘要

Disclosed is an improved alpha calcium sulfate hemihydrate. Methods of producing an improved powdered calcium sulfate hemihydrate (CaSO4.bullet.1/2H2O) [alpha-type] compound are disclosed, at least one meth od including forming calcium sulfate dihydrate (CaSO4.2H2O) into a briquette under high pressure, calcining the briquette to transform the calcium sulfat e dihydrate to calcium sulfate hemihydrate [alpha-type], drying the calcium sulfate hemihydrate [alpha-type] briquette, and optionally grinding the briquette. Also disclosed are methods of producing an improved gypsum plaste r including producing the disclosed powdered calcium sulfate hemihydrate [alph a- type] and mixing the powdered calcium sulfate hemihydrate [alpha-type] with water.