Method for dewatering phosphate slimes
Abstract
Abstract A method for dewatering phosphate slimes and recovering a liquid solution involves adding a calcium sulfate hemihydrate to the slimes, mixing the resulting admixture to effect formation of calcium sulfate dihydrate crystals in the admixture, and recovering a liquid solution from the resulting crystal-containing admixture. The calcium sulfate hemihydrate addition may be followed by addition of calcium sulfate dihydrate. The calcium sulfate hemihydrate addition may be preceded by acidification of the slimes to pH 1-3 with sulfuric acid, which addition may be followed by the addition of other calcium salts to the slimes. A sufficient amount of calcium oxide or calcium carbonate or both may be added to the recovered liquid solution to raise the pH of the liquid solution to a value above about 6.0. Mixing permits calcium phosphate salts to precipitate, allowing for separately recovering the calcium phosphate salts and a dephosphated liquid portion.
Inventors
- 👤 Krishnapillai V. Nair
- 👤 Ponisseril Somasundaran
Bibliographic Details
Claims Analysis
Total Claims: 9References Cited (Backward Citations)
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