火电厂燃煤产物中关键微量元素富集特征研究  

Enrichment Characteristics of Critical Trace Elements in Coal Combustion Products of Power Plants

作　　者：朱士飞[1,2] 毛礼鑫 张静 曹磊[1,3] ZHU Shifei;MAO Lixin;ZHANG Jing;CAO Lei(Jiangsu Design Institute of Geology for Mineral Resources,Xuzhou,Jiangsu 221006;CNACG Key Laboratory of Mineral Resource in Coal Measures,Xuzhou,Jiangsu 221006;Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process,Ministry of Education(China University of Mining and Technology),Xuzhou,Jiangsu 221008)

机构地区：[1]江苏地质矿产设计研究院,江苏徐州221006 [2]中国煤炭地质总局煤系矿产资源重点实验室,江苏徐州221006 [3]煤层气资源与成藏过程教育部重点实验室(中国矿业大学),江苏徐州221008

出　　处：《中国煤炭地质》2024年第3期21-26,共6页Coal Geology of China

基　　金：江苏省地质学会学术研究课题和学术交流方向资助项目(JSDZXH-P2022-03);安徽省现代煤炭加工技术研究院开放基金项目(MTY202206);江苏地研院科技项目(JSY-2022-J02)。

摘　　要：煤系共伴生战略性关键元素可在燃煤产物中富集,研究燃煤产物中关键元素的富集特点可为元素的预富集和提取利用提供依据。以我国东西部不同火电厂燃煤产物为例,采用波长色散荧光光谱仪(AxiosmAX)、电感耦合等离子体质谱仪(iCAP-Qc)测试了燃煤产物中常量元素和关键微量元素的含量,分析了燃煤产物中关键微量元素分布富集的一般性规律。结果表明:①粉煤灰中主要常量元素为Si、Al、Fe,三者氧化物占比达87.79%;微量元素中稀土元素、锂、镓、铀、锗的含量分别为456.95μg/g、163.58μg/g、49.07μg/g、8.67μg/g、4.59μg/g,除铀、锗外均高于世界煤灰平均值。②常量元素中P趋向富集于细灰中,Fe、Ca更易富集于粗灰中;稀土元素分布模式保持一致,且在细灰中的含量高于粗灰,锂、镓、铀、锗均在细粒燃煤产物中更为富集,分异系数分别为1.17、2.45、1.53、2.14。③数理统计分析表明,煤中稀土元素与无机矿物相关,且富集于燃煤产物的非磁性组分中;锂主要与黏土矿物有关,燃烧后主要以LiAlO2的形式存在;镓、铀赋存形式不单一,与黏土矿物有一定的关系;锗与无机相相关性弱,表明其主要与有机质结合。The critical trace elements associated with coal measures can be enriched in coal combustion solid residues.A basis can be provided for the preenrichment,extraction and utilization of critical trace elements by studying their enrichment and differentiation characteristics in coal combustion products.Taking coal combustion products of different power plants in eastern and western China as examples,the contents of major elements and trace elements in coal combustion products were measured by Wavelength dispersive fluorescence spectrometer(Axios mAX)and inductively coupled plasma source mass spectrometer(iCAP-Qc)respectively,and the general law of distribution and enrichment of key trace elements in coal products was clarified.The results show that①the main constants elements in fly ash are Si,Al and Fe,and their oxides account for 87.79%.The contents of rare earth elements,lithium,gallium,uranium and germanium are 456.95μg/g,163.58μg/g,49.07μg/g,8.67μg/g and 4.59μg/g,respectively,which are all higher than the world average value of coal ash except uranium and germanium.②Phosphorus tends to be enriched in fine ash,while Fe and Ca are more likely to be enriched in coarse ash.The distribution pattern of rare earth elements is consistent in different samples,and the content of rare earth elements in fine ash is higher than that in coarse ash.Lithium,gallium,uranium and germanium are more enriched in fine coal combustion product,and their differentiation coefficients are 1.17,2.45,1.53 and 2.14,respectively.③Mathematical statistical analysis shows that rare earth elements are related to inorganic minerals and are enriched in non-magnetic components.Lithium is mainly related to clay minerals and exists mainly in the form of LiAlO2 after combustion.The occurrence forms of gallium and uranium are not simple,and have a certain relationship with clay minerals.The weak correlation between germanium and inorganic indicates that germanium is mainly combined with organic matters.

关 键 词：燃煤产物 稀土元素 关键元素富集 

分 类 号：P618.11[天文地球—矿床学]