Experimental Study Of Phosphate Beneficiation Of Low Grade Silica Gel Yunnan Yuxi

Collophane usually associate with silicate and carbonate minerals cemented symbiosis, and disseminated size is fine, therefore, mineral monomer dissociation is more difficult. Meanwhile, cellophane contains not only silicate minerals, but also contains dolomite, calcite and other carbonate mineral impurities, the floatability of which is close to apatite. Combined with gangue composition complex and fine disseminated extent, the separation of collophane becomes very difficult. On the reasonable development and utilization of low grade cellophane, there is a certain guiding significance for the experimental research.The ore studied in this paper is from Yuxi, Yunan Province, mainly irregular grained disseminated, gangue minerals and collophane are cement symbiosis. The multi-element analysis result showed that the main components are P2O5, SiO2, CaO, MgO, Fe2O3and Al2O3, accounted for more than90%of the total mass, and the content of P2O5, SiO2and MgO is21.98%,31.34%and1.54%, respectively. The test samples has the characteristic of low content of MgO and gangue minerals are dominated by quartz, belonging to high silicon and low magnesium phosphate ore, which is different from the feature of high magnesium content and dolomite-based.The characteristic of phosphate mineral composition and sieve analysis results show that there is a certain clay minerals phenomenon, and the distribution of P2O5, MgO and SiO2in particle size is uniform. So preliminary desliming would cause P2O5losses in the fine fraction. Through the comparison of reverse flotation, straight flotation, straight-reverse flotation and double reverse flotation, the experimental results showed that the straight-reverse process was more reasonable. First separated phosphate material and dolomite to achieve desiliconizing in straight flotation, then inhibited phosphate material to separate dolomite in reverse flotation to drop magnesium, thus phosphate material was enriched. There is strong collected ability for carbonate minerals of KPF, could greatly improve flotation recovery. In order to ensure the recovery and grade, adopted the open process of middling reelection for its larger amount, and eventually obtained satisfactory index without adding collector in reverse flotation for its low magnesium content. When the grinding fineness-200mesh accounted for96.6%, the grade and recovery of P2O5in concentrate is27.68%and83.04%with straight-reverse flotation, and the content of MgO is0.62%.