Concentration of low-grade wolfram from Degnan, Rajasthan

Abstract

A low grade wolfram ore assaying 0.11 percent WO3, with quartz as the principal gangue mineral was received for beneficiation tests. Jigging of the -10+28 mesh fraction, followed by tabling and magnetic separation, yielded a concentrate assaying 48.79 percent WO3 with a recovery of 35.5. percent. Tabling the -28+65 mesh fraction obtained from the above, followed by magnetic separation , produced a magnetic concentrate assaying 59.51 percent WO3 with further recovery of 10.8 percent by weight ,when tabled, was found to contain very little wolfram ,indicating that this fraction could be straightaway screened and rejected, The two concentrates obtained above when mixed gave a combined concentrate assaying 50.9 percent WO3 with a recovery of 46.3 percent. Jigging performed as above, followed by tabling of the crushed jig-middling together with the -28+65 mesh fraction of the ore, and magnetic separation of the table concentrate assaying 61.0 percent WO3 with a recovery of 48.2 percent. Straight tabling the ore ground to -35 mesh produced a concentrate improved the grade to 66.3 percent WO3 for a loss in recovery of 2.4 percent. Humphrey's spiral treatment followed by gave a combined concentrate, assaying 59.02 percent WO3 with a recovery of only 37.5 percent.