某硅钙型萤石矿工艺矿物学特征及选矿试验

Process Mineralogy Characteristics and Mineral Processing Technology of Fluorite Ore

浙江金华某萤石矿中萤石、石英与方解石共生,属于细粒嵌布的难选矿石。为有效开发利用该萤石矿产资源,对其进行系统工艺矿物学研究。结果表明,该萤石矿石中目的矿物萤石质量分数在51%左右,主要杂质矿物石英为36%,方解石为9%。粗粒且较纯净萤石含量较少,多数为微细粒,石英和方解石多以包裹体的形态赋存在萤石颗粒内部,嵌布关系复杂,萤石矿物颗粒单体解离较难,磨矿粒度过细易造成微细粒矿泥罩盖和互凝现象,对萤石浮选和回收不利。基于此,对该萤石矿石进行多段磨矿多段浮选,同时在微细粒的浮选过程中强化矿物颗粒分散性,以碳酸钠作为浮选pH值调整剂和分散剂,采用两段磨矿、精选Ⅰ尾矿和粗选尾矿丢尾、其余中矿集中返回至再磨的全流程闭路试验,最终得到萤石精矿CaF_(2)品位为97.15%、回收率为65.46%,CaCO_(3)质量分数为0.95%,SiO_(2)质量分数为0.76%,产品质量达到YB/T 5217-2019《萤石》中FC-97A等级要求。

A fluorite ore in Jinhua city,Zhejinag province is symbiosis of fluorite,quartz and calcite,which is a refractory ore with fine grains.In order to effectively develop and utilize the fluorite mineral resources,the process mineralogy of fluorite was studied systematically.The results show that the content of the target mineral fluorite is about 51%,the main impurity mineral quartz is 36%,and the calcite is 9%.Content of the coarse grain and purer fluorite is less,mostly the microgranular,quartz and calcite fluorite particles more rich in inclusions form inside,disseminated relation of complex,the dissociation of fluorite mineral grains are difficult,and the excessive grinding size is easy to cause the microgranular slime covered and mutual condensation phenomenon,causing adverse effects on the fluorite flotation and recycling.In order to obtain high grade fluorite,the fluorite ore needs to undergo multi-stage grinding and multi-stage flotation.At the same time,the dispersion of mineral particles needs to be enhanced in the process of micro-fine flotation.On the basis of process mineralogy research,using sodium carbonate as flotation environment pH adjusting agent and dispersant,adopting two stages of grinding,tailings of cleaning I and roughing were lost and concentration of middlings was again returned to the whole process of closed-circuit grinding test,we can obtain fluorite concentrate with CaF_(2)grade of 97.15%and recovery rate of 65.46%,0.95%CaCO_(3),0.76%SiO_(2),product quality reaches the FC-97 requirements of YB/T 5217-2019 standard.The results provide a technical basis for the beneficiation of the fluorite ore.