Study On A New Technology And Mechanism Of Scheelite Mud-sand Ore Sorting

The scheelite is brittle, mostly being fine-grained disseminated, which make it easier mudding during the beneficiation process, and is associated with calcic gangue minerals having the similar flotability, such as fluorite and calcite, resulting in the difficulties of recovering scheelite and severe loss of fine-grained scheelite. To solve this problem, the new technology of "desliming-mud-sand ore sorting " was used in this paper, with the flotation method of GY, which was carried out by the flotation experiments of Shizhuyuan380plants scheelite flotation operation ore. Also the mechanism of mud-sand ore sorting and shear-flocculation of micro-fine scheelite recovery was studied, by the means of pure mineral flotation experiments, flotation rate constant determination, Zeta potential measurements, infrared spectroscopy and interaction between the mineral particles.The results of pure mineral tests showed that:The combination of collector GYB and GYR could improve the scheelite flotation selectivity and collecting capability. And micro-fine scheelite could be effectively recovered through the shear-flocculation.The experimental results of actual ore tests showed that:When the rate of desliming was15percent, using the water glass and aluminum sulfate as inhibitors, lead nitrate as an activator, the combination of GYB+GYR as collectors, when scheelite feed ore of Shizhuyuan contains0.46%WO3, the process of mud-sand ore sorting was carried out, mud and sand obtaining good technical indicators with the WO3grade and recovery of sand concentrate achieved to28.32%and78.04%, mud concentrate1.51%and40.77%,as well as the total comprehensive scheelite concentrate WO3grade is11.60%, WO3recovery is71.92%.Mechanism studies showed that:The highest k value of scheelite of the grain size portions was-0.037～+0.001mm, the least k value was the finest grain size portions. The grain size portions of-0.037～+0.001mm had a good selectivity in the flotation process with selective index of being50.86; The grain size portions of-0.001mm had a poor selectivity in the flotation process with selective index of being1.8. If the less of relative amount of the fine particles, the better of the flotation selectivity. Using the process of mud-sand ore sorting could reduce harmful effects of fine slimes to the main flow of scheelite flotation, improving flotation selectivity. The analysis of Zeta potential, shear-flocculation and hydrophobic showed that the variation of shear-flocculation with pH values of micro-fine scheelite was similar only with hydrophobic variation with pH values. The chemical absorption of collector of GYB and GYR took place on the surface of scheelite, making the surface hydrophobic. Hydrophobic is the fundamental factor for scheelite particles to form stable flocs, the shearing is the most external factor for hydrophobic particles to form stable flocs.28Figures,18Tables,97References.