Research On Flotation Technology For Yunnan Malipo Low Grade Scheelite Containing Sulfide And Carbon

Our country's tungsten resources are abundant and rank the first in the world, but with heavy exploitation in the recent decades, wolframite resources are used up nearly, therefore more and more people begin to pay attention to scheelite resources. Most of our country's scheelite ores are low-grade skarn type scheelite and disseminate fine-grained, with associating with a variety of iron, copper and etc sulfide minerals, which results in being difficult to recycle it. Therefore, the study of low-grade scheelite flotation technology for the recovery of tungsten resources will produce important practical significance.Malipo Jin Wei scheelite ore of Yunnan province is gneiss-type scheelite ore and grade of WO3 is only about 0.16%, belonging to low-grade scheelite ore, with valuable metals and complex gangue mineral composition, and varieties of gangue minerals being most proportion; tungsten forms is scheelite and wolframite, being respectively 78.21% and 20.41%. Wolframite account for a large proportion of the total, but the ore grade of wolframite is only 0.03% so that it is hard for recycling scheelite and wolframite together; scheelite ore particle size is fine-unevenly distributed; there are some good crystal graphites in the ores, which influence the removal rate of sulfide ore. Tungsten Ores belonging to "poor", "fine ", "complex" scheelite are hard to recycle them.Through the investigation of the dressing plant, we found that the main problems are as follows:1) after grinding and classification, the particle of ores still coarse and concentration of the slurry is high, too.2) in spite of ore containing large amounts of graphite, which influence sulfur removal rate and flotation of the scheelite get also more difficult.3) because of not enough the depressor in the course selection, lots of pyrrhotite, apatite, calcite, fluorite and so on gangue minerals mixed with coarse scheelite concentrates, so that in the next cleaning operation, separation of scheelite and gangue minerals increases more difficulty.Wei scheelite as raw material in this paper, by ore mineralogy study, and then we carry out a comprehensive, further and systematic on study of flotation separation characteristics. First, for low-grade sulfur and carbon-containing scheelite ores, we design a "partial selective-bulk flotation of carbon sulfur-rough selection of scheelite-temperature selection of coarse scheelite concentrate room" the process scheme, and then we conduct a comprehensive study of scheelite flotation. Finally, we make sure that we apply combination of kerosene+butyl xanthate+ammonium dibutyl dithiophosphate as collector in the flotation processing of sulfur ores and obtaining tungsten tails brought into election operation of the scheelite; Through a roughing and two scavenging, using Na2CO3 as pH regulator, modified silicate as gangue depressor and 731 as white tungsten collector in the rough selection; then the next processing, using water glass as a depressor in the cleaning, after a blank selection, five cleaning selections, getting scheelite concentrate. In the end, through the closed-circuit test we obtain a yield of 0.19%, grade WO352.72% and 62.30% recovery of tungsten concentrate in crude ore grade WO30.157%.