氧化预处理技术在铜钼硫化矿浮选分离中的研究进展

黄铜矿和辉钼矿是两种典型的硫化矿, 其浮选分离一直是业界关注的焦点。硫化矿易氧化, 矿物表面氧化程度和氧化产物类型对其浮选行为有重要影响。黄铜矿、辉钼矿在浮选之前进行氧化预处理, 它们会产生不同程度的氧化和不同类型的氧化产物, 这些原因使矿物的表面原有的性质发生改变, 从而改变矿物固有的浮选行为, 实现黄铜矿和辉钼矿的浮选分离。论文介绍了黄铜矿、辉钼矿的表面特性, 分析了其表面氧化机理, 综述了铜钼硫化矿氧化浮选分离的研究现状, 旨在为铜钼硫化矿物绿色、高效浮选分离提供一定的借鉴。     

中高温混合菌浸出永平低品位铜矿石的研究

采用包括中高温嗜热铁质菌、喜温嗜酸硫杆菌和嗜热硫氧化硫化杆菌的混合菌群在45 ℃条件下浸出永平低品位铜矿石, 并对矿浆浓度、转速和pH值等工艺因素进行了优化, 在最佳浸出条件下对混合菌的浸出行为进行了研究。结果表明:该混合菌群在矿浆浓度150 g/L、转速190 r/min、pH=2.0时, 浸出第6 d时铜的浸出率达到94.26%, 浸出第24 d铜浸出率达到99.79%。研究还发现中高温混合菌可以有效消除钝化膜的生成, 影响浸出率的主要因素是矿浆浓度。     

低品位黄铜矿在嗜热布氏酸菌下的循环伏安分析

电解液中含与不含布氏酸菌时,采用循环伏安法研究了黄铜矿-碳糊电极与电解液之间的电化学行为,并探讨了温度、阴极电位、Fe2+和Cu2+对循环伏安曲线的影响. 结果表明,低品位黄铜矿在0.45 V出现生成多硫化合物的氧化峰,在-0.25和-0.43 V出现生成Cu5FeS4和Cu2S的还原峰. 温度升高促进黄铜矿氧化分解,65℃时的峰电流为35℃时的2倍. 添加适量Fe2+和Cu2+能促进黄铜矿的氧化分解.     

非洲某硫化铜钴矿选矿综合回收技术研究

非洲某铜钴矿原矿含铜2.11%,钴0.090%,其中的钴品位较低,难以有效回收,且含钴矿物嵌布粒度不均匀,与黄铜矿、黄铁矿共生关系复杂,严重影响选矿过程中含钴矿物的综合回收。根据原矿性质,采用\"铜钴依次优先\"浮选工艺流程,结合使用高效选择性捕收剂BKAP,实现了铜、钴资源的综合回收,实验室所得铜精矿铜品位35.08%,铜回收率93.42%;钴精矿钴品位2.27%,钴回收率51.82%。     

铜铅硫化矿物浮选分离中铅抑制剂的研究进展

硫化铜铅矿石的浮选分离问题是矿物加工工程领域的热点和难点,文章针对浮选抑制剂的研究进展,从无机抑制剂、有机抑制剂、组合抑制剂和新型抑制剂四个方面,对硫化铜铅矿石浮选分离中铅抑制剂的研究成果进行了概述。分析指出,利用浮选药剂分子设计理论开发出新型铅抑制剂,使用组合抑制剂是未来硫化铜铅矿石浮选分离的重点研究方向。     

甘肃某铜矿选矿新药剂应用研究

甘肃某铜矿为单一含铜浸染状黄铁矿石,研究结果表明,部分呈单体解离状态的细粒级铜矿物和黄铜矿富连生体进入尾矿是导致铜矿物损失的主要原因。通过试验研究,在不改变现场生产流程的情况下,采用捕收能力较强的新型药剂D60为捕收剂,小型试验和矿浆样验证试验均取得了良好的技术指标,新药剂方案铜回收率较现场药剂方案铜回收率均提高1%以上,可有效提高铜回收率。      

某含铜尾矿粗砂工艺矿物学特征及选矿试验研究

为查找铜损失在尾矿中的原因并制定选矿回收工艺,对某低品位含铜尾矿粗砂进行了工艺矿物学分析和选矿试验研究。结果表明：含铜矿物主要是黄铜矿（CuFeS2）,嵌布粒度微细且呈浸染状分布,未能充分单体解离而损失在尾矿中。经过选矿优化试验确定粗尾砂可采用立式搅拌磨,使微细粒级铜矿物充分单体解离;然后,采用优先浮选工艺回收铜,闭路试验可获得Cu品位18.02%、Cu回收率41.05%的铜精矿。     

中温及嗜热菌对不同成因黄铜矿浸出行为的影响

以斑岩型黄铜矿和矽卡岩型黄铜矿为研究对象,考察了嗜酸氧化亚铁微螺菌(L f)和嗜热硫氧化硫化杆菌(S t)对不同成因黄铜矿浸出行为的影响。结果表明,在2种不同细菌浸出体系中矽卡岩型黄铜矿均表现出比斑岩型黄铜矿浸出率高;S t浸出2种不同成因黄铜矿的效率均比L f的好。通过对不同浸矿时间黄铜矿浸出渣的XRD检测并结合黄铜矿浸出过程反应步骤的分析表明,2种细菌浸出不同成因黄铜矿的机制相同,细菌的代谢途径及反应温度是影响同类成因黄铜矿浸出率和代谢产物差异的主要原因。S t作用下浸出后期黄铜矿表面有黄钾铁矾生成,而L f浸出体系黄铜矿表面主要是S的不断积累。同种浸矿菌种浸出不同成因黄铜矿时,矽卡岩型黄铜矿在浸出第15 d有S生成,斑岩型黄铜矿在S t浸出体系S生成的时间更晚,在L f浸出体系S的生成量则更少,推测矿物性质是引起其差异的主要原因。     

Kinetics of chemical leaching of chalcopyrite from low grade copper ore: behavior of different size fractions

The kinetics of the chemical leaching of copper from low grade ore in ferric sulfate media was investigated using the constrained least square optimization technique.The experiments were carried out for different particle sizes in both the reactor and column at constant oxidation-reduction potential (Eh),pH values,and temperature.The main copper mineral was chalcopyrite.About 40％ of Cu recovery is obtained after 7 d of reactor leaching at 85℃ using -0.5 mm size fraction,while the same recovery is obtained at 75℃ after 24 d.Also,about 23％ of Cu recovery is obtained after 60 d of column leaching for +4-8 mm size fraction whereas the Cu recovery is as low as about 15％ for +8-12.7 and +12.7-25 mm size fractions.A 4-stage model for chalcopyrite dissolution was used to explain the observed dissolution behaviors.The results show that thick over-layers of sulphur components cause the parabolic behavior of chalcopyrite dissolution and the precipitation of Fe3+ plays the main role in chalcopyrite passivation.In the case of coarse particles,transformation from one stage to another takes a longer time,thus only two stages including the initial reaction on fresh surfaces and S0 deposition are observed.     

Characterization and kinetic study on ammonia leaching of complex copper ore

Ammonia leaching kinetics of a complex Cu-ore assaying 8.8% Cu and 36.1% Fe was examined. Mineralogical characterization indicated that the major phase of the ore was siderite with chalcopyrite as the major sulfide mineral. The effects of parameters such as agitation, temperature, NH₃ concentration, particle size and oxygen partial pressure (p_O2) were investigated. Under the standard leaching conditions of 125–212 µm particle size, 120 °C, 1.29 mol/L NH₃ and 202 kPa of p_O2, about 83% Cu could be selectively extracted in 2.5 h. However, when using higher NH₃ concentration and lower particle size, more than 95% extraction was achieved. The leaching process was found to be surface reaction controlling. The estimated activation energy was (37.6±1.9) kJ/mol and empirical orders of reaction with respect to p_O2 and [NH₃] were about 0.2 and 1, respectively.