非洲中南部某镍矿石工艺矿物学性质

对非洲中南部某镍矿石的工艺矿物学特征进行研究，为合理有效利用该镍矿石提供依据，采用X射线荧光光谱分析、多元素分析、X射线衍射和镜下鉴定等方法，分析了矿石的化学成分、矿物组成、嵌布特征、矿石结构构造以及主要金属矿物磁黄铁矿和镍黄铁矿的嵌布粒度等。研究结果表明：该矿石中镍含量高达3.42%，以镍黄铁矿的形式存在；硫化镍矿嵌布粒度较粗，+150 μm粒级含量为38.20%，+75 μm粒级含量达68.58%，但分布不均匀。该矿石镍品位高且含镍矿物嵌布粒度相对较粗，属于易选矿石类型，白云石、滑石等含镁脉石矿物的存在是影响该镍矿分选的主要因素。

Process Mineralogy of a Nickel Ore in South Central Africa

In order to study the processing mineralogy characteristics of nickel ore in South Central Africa, and provide a basis for its reasonable recovering，use the X ray fluorescence spectrum analysis, multi element analysis, X ray diffraction and microscopic examination and statistics, the chemical and minerals composition and embedding characteristics, ore structure and texture and the granularity of pyrrhotite and nickel pyrite are analyzed.According to the results of XRF analysis:The main chemical compositions of the ore are iron, sulfur, silicon, magnesium, calcium, nickel, copper, aluminium,cobalt and so on,in these elements,the nickel can be used in industrial, and the copper, cobalt, sulfur are valuable elements,which can be recovered comprehensively.The results of multi-element analysis showed that the content of nickel in the ore is 3.42%,the main associated impurities are SiO₂, MgO and CaO.Through X-ray diffraction analysis, microscopic detection and statistics, concluded that the main mineral composition of the ore is pyrrhotite with a content of 76.06%, nickel-bearing pyrite with a content of 9.74%, and gangue minerals with magnesium silicate minerals such as dolomite, talc and chlorite with a content of 7.75%, 2.39% and 1.43%, respectively.The study on the structure and dissemination characteristics of the ore showed that the dissemination size of pyrrhotite in the ore is mainly coarse and uniform, and the dissemination size of nickel pyrite is also coarse, but not uniform. Pyrrhotite,nickel pyrite and chalcopyrite coexist closely,and have interpenetration,encapsulation and substitution phenomena.They are closely distributed in aggregates, forming massive ore structures.In addition, a small number of pyrrhotite, nickel pyrite and magnetite are distributed in gangue minerals in granular form, showing disseminated structure.Some gangue minerals are veined along pyrrhotite and nickel pyrite. Intergranular, fissure filling cementation forms vein-like, reticular structure.The results of particle size measurement and analysis of pyrrhotite and nickel pyrite in ore under microscope show that the pyrrhotite in ore is mainly coarse grained, mainly distributed in the range of +75 micron, the content of +150 micron is 92.76%, the content of fine grains is less, and the distribution is uniform; The size of pyrrhotite is coarse, but the distribution is not uniform,except for the content of +150 micron is 38.2% and the content of pyrrhotite is more than that of +150 micron. Except for 16.63% of -150+100 μm grain size, the content of other grain size ranges is about 10%.On the whole,the ore with high nickel grade,the granularity of nickel bearing minerals is relatively coarse, which is easy selection ore.The existence of magnesium bearing minerals, such as dolomite and talcum,affect the separation of nickel ore.