中文摘要：

通过红土镍矿含碳球团的还原实验,采用X射线衍射、扫描电镜、能量散射谱和化学成分分析等手段,研究红土镍矿原料性质、还原产物的物相转变和显微结构的变化规律,探讨红土镍矿的真空碳热还原特性。红土镍矿原料性质研究表明：在973 K时干燥焙烧红土镍矿能够改变矿物的微观结构,促进矿物的分解,提高矿物的还原性。实验结果表明：还原过程产物主要有SiC、Fe-Si合金、2MgO.SiO2、Mg和SiO气体,其中SiO挥发至冷凝系统歧解生成Si和SiO2,金属Mg在冷凝系统受到O、Si元素的轻度污染;添加剂CaO和CaF2可显著改善红土镍矿的还原效果,促进了镍铁颗粒的聚集。

英文摘要：

We addressed the carbothermic reduction of the saprolite nickel laterite ore in vacuum.The microstructures and properties of the saprolite nickel laterite grains and the reduction products and the phase transformation involved were characterized with X-ray diffraction,scanning electron microscopy-energy dispersive spectroscopy.We found that roasting of saprolite nickel laterite at 973 K promoted decomposition and reduction of the minerals,possibly because of changes in its microstructures.The results show that the reduction mainly produced SiC,Fe-Si alloy,2MgO·SiO2,Mg and the gaseous phased SiO.In the condensation area,SiO disproportionated into Si and SiO2;and Mg was slightly contaminated by O and Si.Moreover,addition of CaO and CaF2 considerably enhanced the carbothermic reduction and enrichment of ferronickel grains.