Abstract
Carrier magnetic separation of fine wolframite (-5μm) was investigated using coarse magnetite (37-53μm, etc.) as carriers and sodium oleate as a surfactant by high gradient magnetic separator. Effects of some factors on the carrier magnetic separation were studied. It was found that the recovery of fine wolframite was significantly increased from about 23% by conventional magnetic separation to 94% by carrier magnetic separation at magnetic flux density 0.14T. The recovery of fine wolframite was improved from 50% to 93% by carrier magnetic separation at 0.27T for a mixture of wolframite (-5μm) and quartz (-10μm) containing 10.9% WO3.
The improved results of magnetic separation were mainly explained by the size enlargement of the fine wolframite due to the addition of carriers and stirring at high speed. The collision energy between the coarse and fine particles is much greater than that between fine particles. Therefore, aggregation be tween coarse and fine particles occurs more easily. The stability of aggregate of particles is also strengthened due to the hydrophobic forces between particles with the addition of sodium oleate.
