钨离子交换工艺中钨锡分离新工艺(Ⅲ)——钨精矿的焙烧预处理研究

在分析SnO2和Cu2FeSnS4碱浸出热力学行为差异的基础上,研究了钨精矿焙烧预处理对锡浸出率的影响。研究表明,苛性钠浸出钨精矿时,SnO2极难浸出,浸出率接近为零,而Cu2FeSnS4的浸出率则高得多,在一般浸出条件下,可高达40%～50%。钨精矿经过氧化焙烧后,可明显降低锡的浸出率,在焙烧温度为700～800℃、焙烧时间为2 h工艺条件下,Cu2FeSnS4所含硫化状态的锡就可完全转化为SnO2。锡的浸出率由5.96%下降至1.05%。     

高锡钨精矿选择性浸出锡、钨工艺研究

研究了采用高压碱浸法从高锡钨精矿中分离锡、钨,考察了浸出温度、碱浓度、浸出时间、液固体积质量比及添加剂用量等对锡、钨浸出率的影响。结果表明:将750℃下焙烧2h的高锡钨精矿进行高压碱浸,在添加剂用量为矿石质量的1.0%、温度150℃、氢氧化钠用量为理论量的3倍、浸出时间2.5h、液固体积质量比1∶1条件下,钨浸出率达98.57%,浸出渣中锡质量分数为3.34%;锡富集于浸出渣中,钨进入溶液,钨、锡得到有效分离。     

低品位锡钨萤石中矿综合回收试验

采用苏打还原焙烧—水浸工艺、硫酸焙烧—水浸工艺从某含锡钨萤石中矿中综合回收钨、锡和氟,考察苏打加入量、还原剂煤与苏打配比,硫酸加入量、碳酸铵加入量以及控制溶液终点pH等对回收的影响。研究表明,采用中矿两次硫酸焙烧——洗矿——碳酸铵浸出——盐酸浸出工艺,分解原料中99.95%的氟,钨总浸出率为98.04%,锡保留率为17.70%。该工艺指标较好,三废可达标排放,经济效益明显。     

低品位钨渣处理工艺研究

采用碳酸钠焙烧—氢氧化钠浸出的方法,从含钨 1.4 %的碱浸钨渣中回收钨,试验研究了浸出温度、反应时间、碱浓度与液固比对钨浸出率的影响.结果表明,在浸出温度 80 ℃,碱浓度 130 g/L, 反应时间 45 min,液固比（指碱液与钨渣的质量比,下同）4:1 的试验条件下,钨的浸出率可达到 90.5 %, 达到了高效浸出钨的目的.该工艺方法流程简单,操作条件温和,回收率高,具有良好的应用前景.      

氢氟酸直接浸出从含钨萤石精矿中提钨试验研究

介绍了湖南某地区含钨萤石精矿采用氢氟酸直接浸出提钨的方法。通过对氢氟酸用量、浸出温度和浸出时间等工艺参数进行研究表明:在加入液固比1.2∶1的氢氟酸溶液(含氢氟酸40%),浸出温度30℃,浸出时间1 h的条件下,钨浸出率可达93%以上。     

复杂钼钨矿石溶浸试验

某钼钨矿石钼、钨品位较低,其中钼含量0.36%、钨含量0.88%,-38μm占90%,矿石中矿物物相复杂、有用矿物粒度小且较为分散,矿物颗粒连生情况极其复杂。采用焙烧—化学浸出的方式回收钨、钼,开展了液固比、药剂用量、浸出温度和浸出时间的研究。研究表明：在液固比6 mg/g、氧化剂A用量10 kg/t、碱性浸出剂B和C用量分别为80 kg/t和9 kg/t、浸出时间4 h、浸出温度80℃的条件下,钼的浸出率为83.79%,钨的浸出率为39%。通过细磨强化,-20.043μm占90%,在同样条件下钼浸出率达到94.11%,钨浸出率为60.74%,取得了较好的浸出效果。     

某含钨粗锡物料钨锡分离试验研究

通过对某含钨粗锡物料工艺矿物学分析,拟定试验方案,开展了脱硫、脱铁、脱杂,产出钨锡混合精矿,并对钨锡混合精矿进行了浮选及水冶试验研究,实现了钨锡有效分离,产出合格钨、锡精矿、硫精矿及铁粗精矿.     

四川平武某结合钨精矿的焙烧浸出

对四川平武某难处理结合钨精矿进行了成分及物相分析,发现其中所含主要矿物为白钨矿(26.47%)、黑钨矿(14.82%)、电气石(47.65%)、石英(11.06%),通过化学分析得出该试样中WO_3含量为32.66%。放大300倍的光学显微照片清晰显示大部分黑钨矿在白钨矿中以细粒嵌布形式产出,因此通过常规选矿方法难以将该结合钨精矿分离以分别获得合格的黑、白钨精矿。在物相分析的基础上,考虑通过湿法浸出的方法充分回收其中的钨元素。通过矿样筛分试验及碳酸钠焙烧浸出条件试验确定了磨矿细度为-74μm占75.68%,碳酸钠用量0.25g·g~(-1)矿样,焙烧时间3h,焙烧温度800℃;浸出时间t~2=30min的纯碱浸出流程,获得钨浸出率97.61%的结果。通过研究纯钨酸钠溶液中CaO的添加量与CaWO_4生成量的关系并结合条件试验结果讨论了浸出过程的返沉现象,试验结果表明高温焙烧导致石灰的生成,会造成浸出液中的WO_4~(2-)发生返沉,导致浸出率的下降,所以焙烧时加入过量的碳酸钠是必要的。     

离子交换法从钨锡中矿提取钨

本文主要研究用717强碱性阴离子交换树脂从钨酸钠溶液中提取钨的工艺,原料为钨锡中矿。通过静态交换实验、正交设计动态实验及多因素分析法找出了最佳吸附条件和淋洗剂组成,并在此基础上作了三柱式小型工艺实验。该法的WO_3总回收率由某厂现行盐酸浸出—氨溶法的88%提高到94%,WO_3产品的化学纯度也由国家标准三级纯(FWO_3-3)提高到国家标准二级纯(FWO3-2)。     

钨精矿碱浸出液中的钨锡分离研究

研究了钨精矿碱浸出液中锡的存在形式及钨锡分离.试验结果表明,浸出液的pH对锡的存在形式有较大影响,溶液pH值越高,SnS2-/3存在比例越低;沉淀剂M115能够高效地从钨酸钠溶液中将SnS2-/3选择性去除,除锡率随试剂用量增加和反应时间延长而增大,随反应温度升高而降低.在试剂用量为理论用量6倍、室温条件下搅拌1 h,锡去除率可达90%以上.     

一种钨湿法冶金清洁生产工艺

在研究从碱性介质直接萃钨的基础上提出了一种新的钨湿法冶金清洁生产工艺，即苛性钠浸出-季铵盐碱性介质直接萃取钨-蒸发结晶生产APT（仲钨酸铵）新工艺。阐述了这种新工艺的实验基础产对该工艺进行了系统的分析。结果表明，与传统的溶剂萃取工艺相比，新工艺的废水排出量大为减少，降低了对环境的污染；同时新工艺还缩短了工艺流程，并大大减小了酸碱等化学试剂的消耗。     

高镍铜阳极泥中硒、碲、铜的顺序脱除

针对高含镍铜阳极泥,采用直接添加氢氧化钠焙烧-碱浸-酸浸流程进行Se、Te、Cu的脱除试验研究,并对过程的反应机理进行了分析。研究发现,加碱氧化焙烧过程中硒化物和碲化物中的Cu变成Cu O和Cu3Te O6;Se、Te分别转变成在碱性溶液中易溶的Na2Se O3和不溶的Ag2Te O3、Cu3Te O6,为Se、Te、Cu的选择性脱除奠定了基础。试验结果表明,最佳焙烧-碱浸的条件为:Na OH剂量为阳极泥的10%,焙烧时间1.5h,焙烧温度500℃。碱浸时间1.0h、Na OH浓度20g/L、碱浸温度80℃、液固比5∶1。在此条件下Se的浸出率为95.50%,碱浸渣中Se的含量从3.93%下降到0.23%。碱浸渣酸浸除铜碲的最佳条件为:H2SO4浓度为90g/L、酸浸温度70℃、酸浸时间1.0h、液固比20∶1;在此条件下,Cu、Te的脱除率分别为96.18%、98.48%。     

硬质合金磨削废料中钨的回收利用研究

采用氧化焙烧-常压(高压)碱浸和苏打焙烧-常压水浸工艺,对硬质合金磨削废料中WC的焙烧浸出工艺进行了研究。XRD分析氧化焙砂,发现生成了难以分解破坏其结构的Fe(Al,Cu,Ti,Co)O.xSiO.2yWO3的多组分复杂固溶体物相,即使采用高温高压碱浸工艺,钨的浸出率也只有33%左右。苏打焙烧,增加碳酸钠量,提高焙烧温度,均可提高WO3浸出率(最高可达99.35%),降低其渣中含量(最低可至0.2%)。XRD分析可知,苏打焙烧可以抑制Fe(Al,Cu,Ti,Co)O.xSiO.2yWO3固溶体结构的形成。     

低品位铝土矿的高效脱硫脱硅工艺研究

通过采用悬浮焙烧-碱浸脱硅的方式对铝土矿进行处理,并研究了焙烧温度、苛碱浓度、碱浸温度对焙烧矿碱浸脱硅的影响。结果表明,悬浮焙烧较优温度为930 ℃,在碱浸脱硅条件下液固比为8∶1,脱硅时间为30 min,苛碱浓度为110 g/L,脱硅温度为95 ℃时,可获得较高脱硅率,可达49.24%。Al₂O₃损失率为2.03%,精矿铝硅质量比可提至8.21,悬浮焙烧的脱硅精矿实际溶出率最高可达94.79%。采用石灰为脱硅剂,对碱浸脱硅后的碱液进行脱硅后,可对焙烧矿进行循环脱硅利用,脱硅后的精矿铝硅比均可达到7以上,从而使碱液实现了循环利用。      

从火法冶炼硅酸钙渣中回收钨钼的试验研究

以某厂火法冶炼硅酸钙渣为原料,在前期探索试验中,采用常压高温碱煮和高温高压碱煮、碱性条件下磷酸盐浸出取得浸出效果不好的情况下,通过采用加碱焙烧-球磨浸出工艺综合回收钨钼,成功实现钨钼高回收率。由于焙烧方法需要采用高温,能耗较高,因此主要进行加碱焙烧条件试验以及探索降低焙烧温度试验研究。经过试验,找到最佳工艺为:原料与Na2CO3和Na2O2的重量之比为10∶5∶1,在800℃下联合焙烧1 h,加水球磨,钨钼的回收率能达到92%以上。     

Caustic roasting and leaching of electric arc furnace dust

Electric arc furnace (EAF) dust is produced when iron and steel scrap is remelted in an electric arc furnace. There are still significant problems associated with the pyrometallurgical and/or hydrometallurgical processes for the treatment of this dust. In the present research, the dust was roasted with caustic soda at low temperatures. It was found that the zinc ferrite (ZnFe₂O₄) in the dust was converted into sodium zincate (Na₂ZnO₂) and iron oxide (Fe₂O₃). In the subsequent dilute caustic leaching process both the zincite (ZnO) and the sodium zincate were soluble and the hematite was relatively insoluble. After roasting and leaching, the zinc recovery was found to be about 95%, while the majority of the iron oxide remained in the leach residue. The lead, cadmium and chromium recoveries were approximately 85, 89 and 37%, respectively, for roasting tests in which moisture was added. Without a moisture addition in roasting, the lead recovery decreased to 63% while the chromium recovery increased to 81%. Based on the experimental results, a hybrid low temperature roasting and dilute caustic leaching process followed by zinc cementation and electrowinning is proposed and discussed. This proposed hybrid EAF dust treatment process provides some potential advantages in comparison to the other hybrid processes which have been described in the literature.     

Leaching of oxidized zinc ores in various media

The leaching of various oxidized zinc ores in different solvents has been studied in laboratory tests by agitation leaching and in some cases by percolation leaching. Some tests have also been carried out on synthetic zinc compounds.The comparison of the leaching of four different Belgian ores in sulfuric acid, sulfurous acid, ammonium hydroxide and sodium hydroxide, shows that the better results are obtained with sulfuric acid and with caustic soda when the concentration of the latter is high enough. All the ores respond very well to leaching except one which is very rich in iron and can be processed only with concentrated caustic soda. Mineralogical studies have shown that smithsonite is completely leached but that hemimorphite is refractory to leaching in any solvent studied.The leaching in alkaline media (ammonia, caustic soda, diethylenetriamine) has been studied on five different ores. It is confirmed that hemimorphite is difficult to dissolve. Good results are obtained only with caustic soda at high temperature. In ammoniacal solutions, the presence of ammonium carbonate enhances the leaching of hemimorphite but decreases the leaching of smithsonite. The optimum concentration of diethylenetriamine is 250 g/l.Caustic soda leaching tests were carried out on pure compounds and showed that ZnO, Zn(OH)₂, PbO, PbCO₃ and 2PbCO₃βPb(OH)₂ dissolve very rapidly and completely, that the leaching of Zn₂SiO₄ is controlled by kinetics and that the leaching of ZnS, PbS and PbSiO₄ is very poor, their solubility product being very quickly attained.The percolation leaching by sulfuric acid has been tested on Belgian ores and the good results obtained support the idea that this kind of ore could be successfully treated in this way.     

基于METSIM软件的钨碱煮工艺流程模拟

简述流程模拟技术在流程工业中的应用现状,介绍METSIM冶金过程模拟系统的特点及用途,并以赣南某钨冶炼工厂的球磨—碱煮工序为对象,建立了基于METSIM软件的WO_3球磨—碱煮工艺的流程模拟仿真系统,并进行了物料衡算、模型准确性验证以及碱煮过程分析。结果表明,基于METSIM软件建立的钨球磨—碱煮流程模拟系统可以准确地模拟整个钨冶炼球磨—碱煮流程,实际生产的WO_3浸出率与模拟计算的WO_3浸出率相对误差为0.35%,通过该模型可以实时了解WO_3浸出过程。