基于煤矸石中锂、镓元素赋存状态的高梯度磁选预富集试验  

Pre-enrichment experiment of high gradient magnetic separation based on lithium and gallium elements in coal gangue

作　　者：孙逢帅 代世琦 王磊[1,2] 邢耀文[1,2] 桂夏辉[1,2] SUN Fengshuai;DAI Shiqi;WANG Lei;XING Yaowen;GUI Xiahui(State key Laboratory of Coking Coal Resources Green Exploitation,China University of Mining and Technology,Xuzhou 221116,China;Chinese National Engineering Research Center of Coal Preparation and Purification,China University of Mining and Technology,Xuzhou 221116,China;School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学炼焦煤资源绿色开发全国重点实验室,江苏徐州221116 [2]中国矿业大学国家煤加工与洁净化工程技术研究中心,江苏徐州221116 [3]中国矿业大学化工学院,江苏徐州221116

出　　处：《洁净煤技术》2024年第1期154-162,共9页Clean Coal Technology

基　　金：国家重点研发计划资助项目(2021YFC2902605)。

摘　　要：我国山西、内蒙古部分矿区煤矸石中蕴藏着锂、镓等战略性关键金属,其锂、镓元素富集逐渐成为研究热点。然而煤矸石中锂、镓含量很低,直接浸出需消耗大量化学药剂,高效、经济的富集锂、镓元素仍存在很大挑战。为提高煤矸石中锂、镓富集效率,针对山西朔州地区煤矸石中锂、镓元素赋存状态和预富集方法展开研究。采用逐级化学提取法、矿物物相组成、矿物解离分析、电感耦合等离子体质谱法、扫描电子显微镜和能量色散光谱,研究了煤矸石中锂、镓元素的赋存状态,利用高梯度磁选探究通过抛除黄铁矿对煤矸石中锂、镓元素预富集的可行性。结果表明,煤矸石主要由高岭土、黄铁矿、石英、方解石、白云母等矿物组成,锂、镓元素主要赋存于硅酸盐类矿物中,黄铁矿中含量较少。原矿中锂质量分数146.37μg/g,镓质量分数25.04μg/g。通过磁选方法抛除黄铁矿可对煤矸石中锂、镓元素预富集,1000 mT时,预富集效果最佳,磁选尾矿中锂质量分数210.63μg/g,为原矿中锂含量的1.45倍,锂回收率88.00%。镓质量分数31.88μg/g,高于原矿中镓元素,镓回收率80.07%。Lithium,gallium and other strategic key metals are endowed in the coal gangue in some mining areas of Shanxi and Inner Mongolia,and the enrichment of lithium and gallium elements has gradually become a research hotspot.However,the content of lithium and gallium in coal gangue is very low,and direct leaching needs to consume a lot of chemicals,so it is still a big challenge to enrich lithium and gallium efficiently and economically.In order to improve the enrichment efficiency of lithium and gallium in the coal gangue,research was carried out on the state of lithium and gallium in the coal gangue in Shuozhou,Shanxi Province,and the pre-enrichment method.Using step-by-step chemical extraction method,mineral phase composition,mineral dissociation analysis,inductively coupled plasma mass spectrometry,scanning electron microscopy and energy dispersive spectroscopy,the Li and Ga elements in the coal gangue were studied,and the feasibility of the pre-enrichment of Li and Ga in the coal gangue by removing pyrite was investigated by using high-gradient magnetic separation.The results show that the gangue is mainly composed of kaolin,pyrite,quartz,calcite,mica and other minerals,and the elements of lithium and gallium are mainly in silicate minerals,with less pyrite content.The lithium content in the original ore is 146.37μg/g,and gallium content is 25.04μg/g.Lithium and gallium elements can be pre-enriched in the gangue through pyrite threw off by magnetic separation.In 1000 mT,pre-enrichment effect is the best,and the lithium in the magnetically selected tailings is 210.63μg/g which is 1.45 times of lithium content,the lithium recovery rate is 88.00%.Gallium recovery rate is 31.88μg/g which is higher than the gallium element in the original ore,and gallium recovery rate is 80.07%.

关 键 词：煤矸石 锂 镓 赋存状态 高梯度磁选 

分 类 号：TD94[矿业工程—选矿]