某难选辉钼矿的浮选溶液化学特性及其调控

发布时间：2019-04-28 11:52

【摘要】：针对该难选辉钼矿中粘土矿物和石膏含量多的特点,以浮选溶液化学特性为研究的切入点,研究难选辉钼矿的浮选行为。通过辉钼矿和高岭石的单矿物浮选试验以及辉钼矿-高岭石的人工混合矿物浮选试验,研究不同的溶液化学环境对二者浮选行为的影响。结合动电位测量、表面润湿性测定、吸附量测量等手段,研究不同的溶液化学环境对矿物的表面性质、颗粒与药剂间作用以及颗粒间相互作用的影响。论文得出以下结论:单矿物浮选试验结果表明:在煤油浮选体系中,酸性和中性条件下,辉钼矿表现出较好的可浮性。矿浆中石膏的存在不利于辉钼矿的浮选,且随着p~(2+)H的增大,影响逐渐增大。在辉钼矿-高岭石的人工混合矿物浮选试验中,高岭石罩盖夹带现象严重,石膏的加入,不仅会影响辉钼矿的浮选,还加剧了这种现象,精矿的品位和回收率进一步降低,降低矿浆的p~(2+)H值有利于浮选效果的提高。三种调整剂,六偏磷酸钠、水玻璃和碳酸钠对于改善矿浆的环境,提高浮选效果有一定的作用。辉钼矿的疏水性随着p~(2+)H的增加逐渐降低。结合矿物的晶体结构分析,以及加入石膏后辉钼矿的表面动电位、表面润湿性和Ca~(2+)吸附量的变化规律可以知道,石膏溶解产生Ca~(2+)会与辉钼矿表面的MoO_4~(2-)发生作用,改变辉钼矿的表面性质,光电子能谱法(XPS)的测试结果也印证了这一点。降低溶液的p~(2+)H值有利于减轻石膏带来的影响。由扩展的DLVO理论的计算可知:pH=6时,在浮选体系下,当加入石膏时,石膏溶解产生的Ca~(2+)压缩了辉钼矿和高岭石表面的双电层,两颗粒间更容易相互吸引。表面动电位的测量结果也印证了这一点。确定两段磨矿,一次粗选八次精选的实验室浮选机浮选流程,降低精选段的p~(2+)H值有利于浮选效果的提高,通过浮选开路试验,当精选段p~(2+)H值为6-7时,可以使最终精矿品位达到48.05%,回收率为36.32%。
[Abstract]:In view of the high content of clay minerals and gypsum in the refractory molybdite, the flotation behavior of the refractory molybdite is studied on the basis of the chemical properties of the flotation solution. The effects of different solution chemical environment on the flotation behavior of molybdite and kaolinite were studied by single mineral flotation test and artificial mixed mineral flotation test of molybdite and kaolinite. Combined with potentiometric measurement, surface wettability measurement and adsorption capacity measurement, the effects of different solution chemical environments on the surface properties of minerals, the interaction between particles and agents, and the interaction between particles were studied. The results of single mineral flotation test show that molybdite exhibits good floatability under acidic and neutral conditions in kerosene flotation system. The presence of gypsum in slurry is not conducive to the flotation of molybdite, and with the increase of p2 H, the influence increases gradually. In the flotation test of molybdite-kaolinite mixed minerals, the inclusion of Gaolinite cover is serious, and the addition of gypsum will not only affect the flotation of molybdite, but also aggravate the phenomenon, and the grade and recovery of concentrate will be further reduced. The reduction of P ~ (2) H value of slurry is beneficial to the improvement of flotation effect. Three regulators, sodium hexametaphosphate, water glass and sodium carbonate, play a certain role in improving the environment of the pulp and improving the flotation effect. The hydrophobicity of molybdite decreases with the increase of P ~ (2) H. According to the crystal structure analysis of minerals and the surface dynamic potential, surface wettability and Ca~ (2) adsorption capacity of molybdite after adding gypsum, we can know the change rule. The dissolution of gypsum to produce Ca~ (2) will react with MoO_4~ (2 -) on the surface of molybdite and change the surface properties of molybdite, which is also confirmed by the results of (XPS) measurement by photoelectron spectroscopy (XPS). Decreasing the P ~ (2) H value of the solution is beneficial to reduce the effect of gypsum. From the calculation of the extended DLVO theory, it can be seen that in the flotation system of pH=6, when gypsum is added, the Ca~ (2) produced by gypsum dissolution compresses the double layer on the surface of molybdite and kaolinite, which makes it easier to attract each other between the two particles. This is also confirmed by the measurement of the surface dynamic potential. The flotation flow of laboratory flotation machine with two grinding stages and eight roughing stages is determined, and the reduction of the p2 H value of the cleaning section is beneficial to the improvement of flotation effect. Through the flotation open circuit test, when the p2 H value of the concentrate section is 6-7, the flotation effect is improved. The final concentrate grade can reach 48.05% and the recovery rate is 36.32%.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD923

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