贵州织金互层型稀土磷块岩工艺矿物学研究

A study on process mineralogy of interbedded REE-rich phosphorite rocks in the Zhijin deposit,Guizhou Province,China

通过对贵州织金稀土磷矿中高品位磷质条带和白云质条带两类矿石的工艺矿物学研究,查明了矿石的矿物组成、稀土元素和微量元素的赋存特性等,着重研究在不同粒级下的不同化学组分的分布情况、富集规律及相互关系,从降Si、Mg、Fe角度考虑,为原矿的破碎工序和选矿方案选择提供依据。研究结果表明,磷质条带属于高品位钙镁质磷块岩,P_(2)O_(5)平均品位为35%,w(MgO)平均为1.37%,w(SiO_(2))平均为5.76%,磷灰石是主要的有用矿物,含量为74.95%,与白云石、石英、方解石、黄铁矿等矿石紧密镶嵌共生;白云质条带其P_(2)O_(5)品位平均为8.35%,Mg含量相对较高,w(MgO)平均为14.58%,w(SiO_(2))平均为8.12%,白云质条带属于低品位钙镁质磷块岩,磷灰石是主要的有用矿物,含量22.99%,这种互层型磷块岩的主要脉石矿物有白云石、石英、黄铁矿等。

By studying the process mineralogy of two kinds of ores,the high graded phosphorous strip and the dolomitic strip,in the Zhijin rare earth phosphate deposit in Guizhou Province,the mineral components,occurrence state characteristics of rare earth elements and trace elements of the ores have been explored.The distribution,enrichment rule and mutual relationship of different chemical compositions at different grain sizes have been studied emphatically.Considering the reduction of Si,Mg and Fe in ores,this study provides the basis for the crushing process of raw ore and the choice of beneficiation scheme.The results show that the phosphorous strips belong to high graded calcium-magnesia phosphorite with an average P_(2)O_(5)grade of 35%,average MgO content of 1.37%and average SiO_(2)content of 5.76%.Apatite is the main useful mineral with its percentage of 74.95%.Apatite is closely embedded and intergrown with dolomite,quartz,calcite,pyrite in ores.The dolomitic strips have the average P_(2)O_(5)grade of 8.35%,the relatively high average MgO content of 14.58%,and the average SiO_(2)content of 8.12%.The dolomitic strip belongs to low graded calcium-magnesia phosphorite,with percentage of 22.99%for apatite which is the main useful mineral.The main gangue minerals of this kind of interbedded phosphorites include dolomite,quartz,pyrite and so on.