贵州西部地区煤中砷的赋存状态及其洗选特性  

The modes of occurrence and washing floatation characteristic of arsenic in coal from Western Guizhou

作　　者：谢宏[1] 聂爱国[1] 

机构地区：[1]贵州大学资源与环境工程学院,贵州贵阳550003

出　　处：《煤炭学报》2010年第1期117-121,共5页Journal of China Coal Society

基　　金：教育部访问学者基金资助项目(教技厅函[2001]3号);贵州省教育厅科研项目(黔教科2001016)

摘　　要：采用光学显微镜、扫描电镜及能谱、电子探针和浮沉试验,结合野外地质特征,对贵州西部煤中砷的存在形式、富集地质因素及可选性进行研究。结果表明:砷不以独立矿物形式存在,砷含量与黄铁矿硫含量呈明显的正相关关系,载砷矿物主要是黄铁矿,砷矿化的重要特点是砷的颗粒极细小,大部分呈类质同象置换硫的形式或固溶体形式或更微细的超显微状态吸附在黄铁矿晶粒外缘的次生增长环边或晶体内部的缺陷和晶隙中;高砷煤中的砷和硫主要来源于黄铁矿,脱硫的同时可有效地将砷剔除,但煤中黄铁矿粒度细,与有机质联系紧密,嵌布方式多样,在浮选粒度范围内,黄铁矿难以解离,即使将煤进一步破碎,分离效果也不明显,因而原煤洗选难以脱除高砷煤中的砷。Using polarizing microscope, scanning electron microscope equipped with dispersive X-ray energy, electronic probe and float-sink experiment, and combining with the field geological features, the preservative status, geological processes for arsenic enrichment and washability of high-As coal in Western Guizhou Province were studied. The results indicate that the mode of occurrence of arsenic is not showed as independent form of mineral, there is an obvious positive correlation between the content of arsenic and pyrite sulfur in coal, most of arsenic in coal is associated with arsenic-bearing pyrite, the significant distinguishing feature of arsenic mineralization includes that the grain of the arsenic is very fine, most of arsenic is occurred in form of isomorphism, solid liquid, super-microscopical sized arsenic adsorbed in the secondary enlargement rim of pyrite or coming into crystal defect and crystal interface of pyrite. The elements of arsenic and sulfur in high-As coal mainly distribute in pyrite, so the concentration of arsenic could be effectively reduced if the sulfur would be removed. However, the grains of pyrite, which have strong organic affinity and complex dissemination feature in coals, are tiny. It is too difficult to separate the pyrite from coal within the range of flotation size. Even the fineness of grinding of coal is increased, the separation effect is not obvious. Therefore, most of As is hard to be removed through physical washing method from raw coals.

关 键 词：贵州西部 高砷煤 赋存状态 可选性 

分 类 号：P618.64[天文地球—矿床学]