Patent ID: 11932569
Assignee: nan
Field: Chemical engineering (Chemistry)
Classification: CPC C  B | IPC B  C

Claim 7:
8. A method for producing a low iron silica sand product comprising an SiO2 content of at least 99.8% by weight, an Fe2O3 content of less than about 0.008% by weight, an Al2O3 content of less than about 0.1% by weight, and a CaO content of less than about 0.05% by weight, the method comprising:
preparing a slurry of crude ore and water, wherein the crude ore has a sand content of about 75% to 80% by weight, a kaolin/mica content of about 15% to 25% by weight, a dark, heavy mineral content of about 1% by weight, and an Fe2O3 content of about 0.5% to 1.0% by weight;
removing particles from the slurry having a size of less than about one hundred forty (140) mesh;
applying shear forces to particles remaining in the slurry to remove contaminant material attached to the particles;
separating the contaminant material from the slurry;
separating sand from the slurry;
drying the sand; and then
feeding the dried sand through a rare earth magnetic separator to produce a low iron silica sand product suitable for all grades of glass production.