含银方铅矿的浮选行为及机理研究

发布时间：2018-03-16 18:01

本文选题：方铅矿　切入点：浮选　出处：《昆明理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：含银方铅矿是典型的一种贵金属和有色金属共伴生的资源,其综合回收对选冶工艺技术有着更高的要求。本论文研究了含银方铅矿单矿物的浮选行为,考察了方铅矿浮选的主要影响因素,在确定的最佳试验条件下开展人工合成含银方铅矿的浮选试验,并与天然含银方铅矿的浮选试验对比,分析银含量对方铅矿浮选的影响,最后通过动电位测定、药剂吸附量测定及矿物表面接触角测量等技术手段进行相关机理探讨,主要试验研究结果如下:含银方铅矿浮选行为与矿浆pH值、pH调整剂、抑制剂及捕收剂等关系密切,在常温条件下、pH为9.0的弱碱性环境中方铅矿浮选效果最好,使用石灰调浆比氢氧化钠和碳酸钠更利于方铅矿浮选,加入适量的强碱弱酸盐亚硫酸钠对方铅矿浮选有促进作用。与其他捕收剂相比,乙硫氮对方铅矿表现出更强的捕收能力。在pH值约为9.0、乙硫氮浓度为80mg/L时方铅矿上浮率最高。在条件一致的环境中,银含量越高的天然或合成方铅矿表现出的可浮性越好,获得的回收率越高。在相同浮选条件下,含银量基本相同的天然与合成方铅矿的浮选回收率差距明显,天然方铅矿的浮选回收率是合成方铅矿的2倍以上。银对合成方铅矿浮选行为的影响与其对天然方铅矿的影响基本相似,即银能提高方铅矿浮选效果,且含银量愈高提高效果愈明显。Zeta电位测定、吸附量测定和接触角测量结果表明,在弱碱性条件下,使用石灰作为pH调整剂,乙硫氮为捕收剂时,方铅矿表面荷正电量最多、捕收剂吸附量最多,表面接触角最大,疏水性最好,浮选指标最高,这些结果验证了单矿物浮选行为试验。各项分析测试及机理分析结果表明,石灰中Ca2+离子能在液-气界面形成微细胶粒粘附于气泡表面或是矿粒与气泡之间,挤压水分子,促使矿粒与气泡间的水化膜破裂,从而使矿粒与气泡吸附更加稳定,更利于矿粒随气泡上浮。在方铅矿-乙硫氮-水体系中添加亚硫酸钠后,矿浆pH值升高,从而抑制方铅矿表面发生自身氧化反应,抑制S2032-生成,增大方铅矿表面疏水性,使其可浮性变好,更利于捕收剂吸附浮选。乙硫氮与银作用形成的金属络合物更难溶,对银的捕收能力强于对方铅矿的捕收能力,其优先与银作用形成疏水性薄膜吸附在方铅矿表面,增大方铅矿表面疏水性和增强捕收剂吸附稳定性,促进方铅矿浮选富集,且银含量愈高这种作用愈明显。
[Abstract]:Galena containing silver is a typical associated resource of precious metals and nonferrous metals, and its comprehensive recovery has higher requirements for processing and smelting technology. The flotation behavior of galena single minerals containing silver is studied in this paper. The main influencing factors of galena flotation were investigated. The flotation experiments of synthetic galena containing galena were carried out under the optimum test conditions, and compared with those of natural galena containing galena, the effect of silver content on galena flotation was analyzed. Finally, the related mechanism is discussed by means of potentiodynamic determination, reagent adsorption measurement and mineral surface contact angle measurement. The main experimental results are as follows: flotation behavior of galena containing silver and pH value of pulp pH adjuster. The effect of galena flotation is the best in the weak alkaline environment with pH 9.0 at room temperature. Lime modified pulp is better than sodium hydroxide and sodium carbonate in galena flotation. The addition of appropriate amount of strong alkali and weak acid sodium sulfite can promote the flotation of galena. The flotation rate of galena is the highest when pH value is about 9.0 and the concentration of ethionitrogen is 80 mg / L. the floatability of natural or synthetic galena with higher silver content is better than that of natural or synthetic galena with higher silver content in the environment with the same conditions. Under the same flotation conditions, the difference between the flotation recovery of natural galena with the same silver content and that of synthetic galena is obvious. The flotation recovery of natural galena is more than twice that of synthetic galena. The effect of silver on the flotation behavior of synthetic galena is similar to that on natural galena, that is, silver can improve the flotation effect of galena. The results of adsorption measurement and contact angle measurement showed that when lime was used as pH adjuster and ethylthionium was used as collector, the positive charge on galena surface was the most. The collector has the highest adsorption amount, the largest surface contact angle, the best hydrophobicity and the highest flotation index. These results verify the flotation behavior of single mineral. The Ca2 ion in lime can form fine colloidal particles at the liquid-gas interface to adhere to the surface of the bubble or between the ore particles and the bubbles, thus squeezing the water molecules, thus promoting the rupture of the hydration film between the particles and the bubbles, thus making the adsorption between the particles and the bubbles more stable. When sodium sulfite was added into the galena-ethylthionitrogen-water system, the pH value of pulp increased, thus inhibiting the autooxidation reaction on galena surface, inhibiting S2032- formation, increasing hydrophobicity of galena surface, and increasing the hydrophobicity of galena surface. The floatability of silver is improved and it is more favorable for the collector to adsorb and floatation. The metal complex formed by the interaction of ethylthionium and silver is more difficult to dissolve, and the ability of collecting silver is stronger than that of galena. The hydrophobic film is adsorbed on galena surface in preference to silver. The hydrophobicity of galena surface is increased and the stability of collector adsorption is enhanced. The higher the silver content is, the more obvious the hydrophobic film is.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD923;TD952

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