Beneficiation study of Eshidiya phosphorites using a rotary triboelectrostatic separator

Abstract

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 A 1, phosphatic bed A 3 and slime samples. The bed A 1 and slime samples were tested without desliming. Two sets of tests were performed using the A 3 sample: one was performed without desliming and the other with the A 3 sample deslimed. RTS separation tests as initially performed on the bed A 1 and slime samples gave products that had essentially the same P 2O 5 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 A 3 phosphate sample; these tests resulted in a highest product grade of 26% P 2O 5. The deslimed A 3 sample showed far more effective separation than the undeslimed A 3 one. In fact, a concentrate of 34% P 2O 5 was obtained from the triboelectrostatic separation of deslimed A 3. The results indicate that with deslimed A 3 P 2O 5 recovery was about 65% for a concentrate of 28% P 2O 5 and about 45% for a concentrate of 30% P 2O 5. 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.