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41.
承德市某钒钛磁铁矿尾矿钛含量较高,潜在回收价值可观。采用化学分析、XRD衍射分析、粒度分析、矿物解离分析仪(MLA)等手段研究了该尾矿的矿物学特性及钛的赋存状态。在工艺矿物学研究基础上,通过试验研究确立了重选短流程回收钛、选钛尾矿差异化分级利用的综合利用技术工艺,获得含TiO234.60%、回收率53.43%的钛铁矿精矿以及产率66.22%的建筑用商品砂,实现了铁尾矿的资源化综合回收利用,有助于矿山与社会环境和谐发展。 相似文献
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Alicja Bakalarz 《Mineral Processing and Extractive Metallurgy Review》2019,40(6):437-446
ABSTRACTThe study involved the chemical and mineralogical analysis of actual tailings production from Lubin Concentrator Plant (KGHM Polska Miedz SA Group). KGHM Polska Miedz SA Group is the world’s leading company that mines and processes sediment-hosted stratiform copper deposits in SW Poland. From the beginning of copper ore mining, the problem of utilization and managing the deposited tailings has been discussed. Annually, all three concentrators produce above 30 million tons of flotation tailings. Lubin Concentrator Plant processes the most complex in upgradeability ore from the other two concentrators. The total loss of copper-bearing minerals in 0.020–0.071 mm size fraction was found to be 52%. The analysis of liberation showed that in fines (–0.020 mm) over 50% of sulfides is released while the amount of totally locked sulfides in the sample constitutes for 65%. The main cause of significant decline in the finest fractions should be attributed to inappropriate flotation time or too low collector dose. Insufficient liberation of sulfides in the coarser fractions can be a reason for the loss of copper in these fractions. The presented results of final tailings confirm the main cause of metal losses in tailings to be very complex mineral properties. 相似文献
44.
为研究某铜镍矿产出的铜镍水淬冶炼渣大宗量处置技术,基于铜镍水淬冶炼渣制备充填胶凝材料的可行性和技术工艺,本研究开展了冶炼渣粉磨试验和激光粒度分析、基于冶炼渣的碱激发胶凝材料配比正交试验、充填体试块单轴抗压强度试验、充填体试块及胶凝材料净浆试块SEM测试,结果表明:该铜镍矿冶炼厂产出的铜镍水淬冶炼渣有一定的火山灰活性,但其火山灰活性较低;实验室配制的碱激发剂对该铜镍水淬冶炼渣激发作用不明显;该冶炼渣的最佳粉磨时间为50min,D(0.5)为28μm。在普通硅酸盐水泥为主要胶凝材料的碱性充填料浆中,冶炼渣的掺入引起了钙矾石生成量的增加,随着粉磨冶炼渣粒径的减小,冶炼渣颗粒表面的溶蚀现象越来越明显。 相似文献
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Metakaolin-based geopolymers were synthesized at Si/Al ratios of 1:1, 1.5:1, 2:1, 3:1, 4:1, and 5:1 by using silica fume as silica corrector to alter Si ratios. The microstructure and strength of these geopolymers were characterized through XRD, SEM, NMR and compressive strength measurements. The dissolving rates of Al and Si species in geopolymerization were measured, and freeze-dried N-A-S-H gel was characterized by FTIR spectra. Modelling and simulation were employed to calculate the binding energy of one Si atom and the total energy of geopolymers formed at various Si/Al ratios. At Si/Al ratio of 2:1, high concentrations of Si and Al species are dissolved from precursors, high contents of Si-O-T linkages are formed and the geopolymer is of high compressive strength. The mechanical strength of geopolymers at various Si/Al ratios is dependent on the formation of N-A-S-H gel, rather than the zeolitic nuclei or silicate derivatives. This study might provide fundamentals for the geopolymerization of mine tailings, which usually possess high Si/Al ratios. 相似文献
47.
福建某铜钼矿尾中K_2O质量分数为5.32%,Na_2O质量分数为2.49%,采用碱法工艺代替传统的酸法工艺进行处理回收长石,工艺流程为反浮选云母—反浮选石英—长石粗精矿磁选除铁。试验最终获得长石精矿中K_2O质量分数为7.48%、总回收率为39.89%,Na_2O质量分数为3.91%、总回收率为43.78%。该长石精矿符合玻璃及玻璃制品、陶瓷、磨料等原料标准。 相似文献
48.
N. PASHIAS D.V. BOGER K. J. SUMMERS D. J. GLENISTER 《Mineral Processing and Extractive Metallurgy Review》2013,34(1):115-122
Abstract Substantial progress has been made recently toward developing environmentally acceptable disposal strategies in the minerals industry. Typically disposal schemes incorporate a mechanical dewatering stage in which the material is concentrated before disposal. At higher concentrations many particulate suspensions will exhibit a yield stress which is of vital importance to the operation of the disposal scheme. The present paper illustrates how the slump test, previously used for determining the empirical flow properties of fresh concrete, has been adopted as a means for accurately measuring the yield stress. The slump test offers a quick and easy way of measuring yield stress without the need for sophisticated electronic equipment, thereby giving plant operators an effective tool for examining yield stress in the field. A simple theoretical model is briefly described and experimental results performed to validate the model. 相似文献
49.
This study offers new insights into two-lift deposition of mature fine tailings under atmospheric drying. The interaction of newly added lift and former lift(s) was evaluated using column experiments in terms of volumetric water content, electrical conductivity (EC), hydraulic conductivity, geochemistry and microstructure. Water content and EC followed the same trend and decreasing of water content appears to be responsible for significant reduction in EC. Evaporation on top of the column reduced the water content to almost zero. The obtained results support the coupling between the hydraulic and chemical processes that should be considered by active operators. 相似文献
50.