Patent ID: 7335254
Filing Date: 2008-02-26
Classification: C04B,Y02W

Abstract:
1. 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.