马来西亚某褐铁矿石工艺矿物学研究

Research on Process Mineralogy of a Limonite in Malaysia

马来西亚某褐铁矿矿石中部分铁矿物嵌布粒度细,磨选难度大,采用传统的磨矿—磁选工艺,精矿回收率偏低。采用传统工艺矿物学研究方法,结合光学显微镜、X射线衍射、化学分析等手段,对矿石的物质组成、元素赋存状态、主要矿物产出特征、矿石的结构构造、粒度组成、物理性质进行了详细研究。结果显示:矿石铁品位为49.66%,主要杂质成分为SiO_(2)和Al_(2)O_(3);矿石中的铁主要以褐铁矿的形式存在,非金属矿物主要为石英,其次为高岭石等;褐铁矿主要以凝胶状、层状(或结核状、鲕状)、蜂窝状、网脉状、树枝状、包裹状、浸染状等形式与脉石连生,连接界面呈齿状交错分布;矿石构造形式复杂,其中的铁矿物多呈不规则粒状、板状和交代氧化假象结构,嵌布粒度极不均匀;样品中+0.28mm粒级含量较高,Fe的分布率可达51.41%,部分铁矿物在各个粒级中均匀分布,铁品位均在50%左右,另外,各粒级中Al_(2)O_(3)的含量较高,品位在5.0%以上,Al_(2)O_(3)的存在对后续铁精矿的质量有一定的影响;矿样松散密度为1250kg/m^(3),堆实密度为1490kg/m^(3),真密度为3390kg/m^(3),堆积角为32.38°,摩擦角为28.33°。基于工艺矿物学研究结果,推荐了悬浮磁化焙烧—磁选新技术。研究结果为该铁矿资源的高效开发利用提供了矿物学依据。

A Limonite ore from Malaysia is embedded with fine particle size,which is difficult to grind and select,resulting that the recovery is low by the traditional magnetic separation process.In this paper,the material composition,element occurrence state,main mineral output characteristics,ore structure and texture,particle size composition and physical properties of a limonite in Malaysia are studied in detail by using traditional process mineralogy research methods,combined with optical microscope,X-ray diffraction,chemical analysis and so on.The results show that the iron grade of the raw ore is 49.66%,and the main impurities are SiO_(2)and Al_(2)O_(3);The iron in the ore mainly exists in the form of limonite,and the non-metallic ore is mainly quartz,followed by kaolinite,etc;Limonite is mainly associated with gangue in gelatinous,lamellar(or nodular,oolitic),honeycomb,net-like vein,dendritic,enveloped and disseminated forms,the interface is toothed and staggered;The ore structure is complex,the iron minerals are irregular granular,tabular and metasomatic oxidation illusion structure,the disseminated grain size is very uneven;The content of+0.28 mm grain in the sample is high,and the distribution rate of Fe can reach 51.41%.Some iron minerals are evenly distributed in each grain,and the iron grade is about 50%.In addition,the content of Al2O_(3)in each grain is high,and the grade is above 5.0%,the existence of Al2O_(3)has a certain effect on the quality of subsequent iron concentrate;The loose density,bulk density and true density of ore sample is 1250 kg/m^(3),1490 kg/m^(3),3390 kg/m^(3),respectively.The accumulation angle is 32.38°,and the friction angle is 28.33°.Based on the above research results,a new technology of suspension magnetization roasting followed by magnetic separation is recommended.This study provides a mineralogical basis for the efficient development and utilization of the iron ore resource.