低阶煤筛分过程中汞及硫元素在不同粒度中的分布规律  

Distribution of Mercury and Sulfur in Diff erent Particle Sizes During the Sieving Process of Low-rank Coal

作　　者：侯向俊 周玲妹[2] 张曼 武正鹏 Hou Xiangjun;Zhou Lingmei;Zhang Man;Wu Zhengpeng(College of Chemistry and Chemical Engineering,Xi'an University of Science and Technology,Shaanxi,710054;School of Chemistry and Environmental Engineering,China University of Mining and Technology(Beijing),Beijing,100083;School of Chemical Safety,North China Institute of Science and Technology,Hebei,065201)

机构地区：[1]西安科技大学化学与化工学院,陕西710054 [2]中国矿业大学(北京)化学与环境工程学院,北京100083 [3]华北科技学院化工安全学院,河北065201

出　　处：《当代化工研究》2023年第20期1-4,共4页Modern Chemical Research

基　　金：中国矿业大学(北京)越崎青年学者资助计划(项目编号:2020QN10)。

摘　　要：燃煤是大气汞污染的主要排放源之一,针对目前煤炭洗选过程中重金属元素迁移脱除研究的不足,选用内蒙古低阶高硫煤和低硫煤样进行筛分试验,通过测汞仪、化学逐级提取、X射线衍射(XRD)、X射线荧光分析(XRF)及扫描电镜等测试方法研究汞元素在煤中的赋存形式及在不同粒度级煤中分布规律。试验结果表明,汞元素在煤中的分布不仅和赋存形式相关,还与矿物质在煤中的组成形式和矿物本身的矿物学性质相关。由逐级化学提取可知,高硫煤与低硫煤中汞主要以二硫化物结合态存在。两种煤中的汞和硫在不同粒度区间的富集和迁移趋势一致;高硫煤中汞含量与灰分在6~13mm粒度区间均为最高,说明汞主要与此粒度区间密度较大的黄铁矿伴生;低硫煤在粒度<0.074mm区域内,灰分及汞的含量较高,因为部分汞在以黏土矿为主的小颗粒中富集。Coal combustion is one of the main emission sources of atmospheric mercury pollution.In view of the current lack of research on the migration and removal of heavy metal elements in the coal washing process,low rank high-sulfur coal(HS)and low-sulfur coal(LS)samples from Inner Mongolia were selected for sieving tests.Mercury analyzer,sequential chemical extraction,X-ray diffraction(XRD),X-ray fluorescence analysis(XRF)and scanning electron microscopy were used to study the mode of occurrence of mercury in coal and the distribution in different particle size.The results showed that the distribution of mercury in coal was not only related to the mode of occurrence,but also related to the composition of minerals in coal and the mineralogical properties of the minerals themselves.From the sequential chemical extraction,it can be seen that mercury in HS and LS mainly existed in disulfide bonded state.The enrichment and migration trends of mercury and sulfur in the two coals were consistent in different particle size ranges.The mercury and ash content in the HS were the highest in the 6~13 mm particle size range,indicating that the mercury was mainly related to pyrite with high density.For LS,the mercury and ash content were higher in the particle size<0.074 mm,because part of the mercury enriched in small particles was mainly composed of clay ore.

关 键 词：汞 硫 筛分 分布和富集 

分 类 号：TD94[矿业工程—选矿] TQ533[化学工程—煤化学工程]