Preconcentration of Low-Grade Ta–Nb Deposit Using Physical Separation Methods

Abstract

Ore from the Jinzhulong Ta-Nb deposit was processed using a combination of gravity concentration and magnetic separation to upgrade the columbitetantalite fines. Two flowsheets, namely for gravity concentration-magnetic separation (the conventional flowsheet) and magnetic separation-gravity concentration (the novel flowsheet), are proposed herein, and the factors affecting the performance of gravity/magnetic separation were studied to optimize the flowsheets. Compared with the conventional flowsheet, the novel flowsheet was more effective for columbite-tantalite beneficiation and beneficial to the comprehensive recovery of nonmetallic minerals. In the novel flowsheet, the sample is ground to size of P 80 = À74 lm then fed into a combination of a low-intensity wet drum magnetic separator and pulsating highgradient magnetic separator to reject nonmagnetic gangue minerals while preconcentrating the paramagnetic columbite-tantalite; the high-gradient magnetic separation concentrates were screened into three size fractions and further upgraded by gravity concentration. The enrichment ratios for Ta 2 O 5 and Nb 2 O 5 were 403.8 and 385.6, respectively.