Beneficiation of a Phosphate Ore Produced by Borehole Mining

摘要

As part of its program to increase the domestic availability of critical minerals, the Bureau of Mines conducted characterization and beneficiation studies on a St. Johns County, Fla., phosphate ore that was mined by borehole mining. Results revealed that the ore from this test mine was mostly sand-size carbonate-fluorapatite and quartz and contained 24.6 percent P2O5. Concentration by various flotation techniques produced phosphate concentrates that ranged, in percent, from 30.0 to 31.4 P2O5, 0.73 to 0.80 MgO, and 2.8 to 7.2 acid insoluble. Recovery of the phosphate from the ore ranged from 89.4 to 96.3 percent.