Alpha-type calcium sulfate hemihydrate compositions and methods of making same
AssigneeG.B.Technologies, LLC
InventorsRobert B. Bruce, Danny W. Cox
Life of this patent
Estimating the term…
Abstract
Disclosed is an improved alpha-type calcium sulfate hemihydrate. Methods of producing an improved powdered calcium sulfate hemihydrate (CaSO4.½H2O) [alpha-type] compound are disclosed, at least one method including forming calcium sulfate dihydrate (CaSO4O.2H2O) into a briquette, calcining the briquette to transform the calcium sulfate 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 plaster including producing the disclosed powdered calcium sulfate hemihydrate [alpha-type] and mixing the powdered calcium sulfate hemihydrate [alpha-type] with water.
Claims8
A method, comprising:
- forming calcium sulfate dihydrate into a briquette having physically bound water in a range from about 15% to 21% by weight of the calcium sulfate dihydrate briquette, wherein forming calcium sulfate dihydrate into a briquette includes providing a pressure of formation greater than 14 megapascal to produce a substantially uncracked briquette that will remain substantially uncracked during calcination;
- adding free water to the calcium sulfate dihydrate briquette, wherein the free water is just greater than 0% up to about 12% by weight of the calcium sulfate dihydrate briquette;
- calcining the briquette;
- transforming the calcium sulfate dihydrate briquette to an alpha calcium sulfate hemihydrate briquette;
- and
- drying the alpha calcium sulfate hemihydrate briquette.
Dependencies are inferred from the claim text.