Beneficiation study of Eshidiya phosphorites using a rotary triboelectrostatic separator

This study was performed to investigate the feasibility of applying a Rotary Triboelectrostatic Separator (RTS) to the beneficiation of Eshidiya phosphate minerals. RTS separation tests were carried out on phosphatic bed A1, phosphatic bed A3 and slime samples. The bed A1 and slime samples were tested without desliming. Two sets of tests were performed using the A3 sample: one was performed without desliming and the other with the A3 sample deslimed. RTS separation tests as initially performed on the bed A1 and slime samples gave products that had essentially the same P2O5 content. This indicated that adsorbed clay particles on the phosphate surface are responsible for the poor separation of un-deslimed phosphates. Better triboelectrostatic separation was observed with the undeslimed A3 phosphate sample; these tests resulted in a highest product grade of 26% P2O5. The deslimed A3 sample showed far more effective separation than the undeslimed A3 one. In fact, a concentrate of 34% P2O5 was obtained from the triboelectrostatic separation of deslimed A3. The results indicate that with deslimed A3 P2O5 recovery was about 65% for a concentrate of 28% P2O5 and about 45% for a concentrate of 30% P2O5. These results clearly show the importance of desliming for effective beneficiation of phosphate by the RTS. A more efficient separation can be expected from optimized operating conditions and circuit configuration.