四川德昌大陆槽氟碳铈矿中Ce、La赋存状态研究

OCCURRENCE STATE OF Ce AND La IN BASTNAESITE AT DALUCAO AREA,DECHANG COUNTY,SICHUAN PROVINCE

大陆槽氟碳铈矿No.1号矿体矿物组成复杂,且风化严重,属难选矿。选矿厂现有的选矿工艺存在品位和收率不能同时保证、生产稳定性差等问题,急需进行改善。针对此情况,本研究在No.1矿体上选取10个代表性矿样进行工艺矿物学分析,通过X射线荧光光谱、X射线粉晶衍射、扫描电子显微镜—能谱、矿物表征自动定量分析系统对矿体样品进行表征,得到了矿物的化学组成、物相组成、嵌布特征和粒级分布的研究,对后续选矿工艺改进提供了支撑。研究结果表明:(1)稀土氧化物主要成分为CeO_(2),La;O_(2),TREO为5.23%,以赋存于氟碳铈矿中为主,脉石矿物主要为长石、方解石、石英、天青石及萤石。(2)在磨矿至75μm时,稀土矿物氟碳铈矿、氟碳铈镧矿仍与主要脉石矿物方解石、天青石、重晶石、萤石等发生二元嵌布,三元包裹的关系。从矿物的比重、磁性考虑,为保证选矿品位和回收率,本矿样应以浮选及强磁选为主,磨矿细度应在-75μm达到80%左右。

The mineral composition of No.1 ore body of Dalucao bastnaesite in Dechang County is complex and the ore is seriously weathered,which makes it difficult to beneficiate.The existing beneficiation process of the concentrator has some problems,such as unguaranteed grade and yield,poor production stability,etc.,which is in urgent need of improvement.X-ray fluorescence spectrum analysis,X-ray powder diffraction,scanning electron microscope,energy spectrum,and mineral characterization technology are used to characterize the process mineralogy of 10 representative ore samples from the No.1 ore body.Thus,the chemical composition,phase composition,distribution characteristics and grain size distribution of minerals are obtained,which provided support for the subsequent improvement of mineral processing technology.The results show that the main components of rare earth oxides in the ore are CeO;and La_(2)O_(2),and TREO is 5.23%,mainly occurring in bastnaesite.Gangue minerals in the ore are mainly composed of feldspar,calcite,quartz,celestite and fluorite.When grinding to 75μm,the rare earth minerals bastnaesite and lanthanite are still in binary distribution and ternary encapsulation relation with the main gangue minerals,such as calcite,celestite,barite and fluorite.The ore samples should be mainly processed by flotation and high intensity magnetic separation in terms of the specific gravity and magnetism of minerals as well as the beneficiation grade and recovery,and the volume of grinded ore should reach about 80%with-75μm fineness.