USE OF MAGNETIC SEPARATION TO BENEFICIATE RARE METAL ORES

摘要

With respect to their magnetic properties, minerals in the rare metal ores under examination can be basically grouped as weakly-magnetic and nonmagnetic. Fig. 1 shows the spectra of their specific magnetic susceptibility values (x). As is evident, the range of changes in percent of ore minerals fluctuates from -0.35 centre dot 10~(-9) m~3/kg (cryolite) to 68.0 centre dot 10~(-9) m~3/kg (biotite) which confirms the considerable difference in magnetic properties for the components in ore minerals and the possibility of using magnetic separation. Using high-gradient magnetic separation (VGMS) it is possible to effectively separate weakly magnetic minerals-with a specific magnetic susceptibility of (200-100) centre dot 10~(-9) m~3/kg within particle sizes from 0.8-0.6 mm to 30-20 mu m other researchers have reduced this range to 12 centre dot 10~(-9) m~3/kg.