燃煤小锅炉燃烧产物的SR-XRF和XANES分析  

SR-XRF and XANES characterization of trace elements and arsenic speciation in combustion products from a small coal-fired boiler

作　　者：包良满[1] 张元勋[1] 金婵[1] 林俊[1] 刘卫[1] 彭岚[1] 陆文忠[1] 李玉兰[1] 张桂林[1] 李燕[1] 

机构地区：[1]中国科学院上海应用物理研究所

出　　处：《核技术》2008年第9期641-647,共7页Nuclear Techniques

基　　金：中国科学院知识创新工程重要方向项目(KJCX3-SYW-N3);中国科学院上海应用物理研究所前沿项目(90070301);国家自然科学基金重大项目(10490182);国家自然科学基金(10375084,10775174);Core University Program of Japan资助

摘　　要：为研究生活锅炉燃煤释放微量元素对环境的影响,应用同步辐射X射线荧光(SR-XRF)测定了锅炉原煤、底灰、飞灰及其PM2.5中V、Cr、Mn、Co、Ni、Cu、Zn、As、Pb等元素含量,探讨了微量元素在煤炭燃烧过程中的转移特性和富集规律。还进行了As的K边X射线吸收近边谱(XANES)测量,研究As在煤炭燃烧排放过程中的价态变化特征。结果表明,V在飞灰中亏损,在底灰富集;Mn、Co在底灰中亏损;Cr、Ni、As、Cu、Pb、Zn等在飞灰和底灰中呈富集状态,As、Cu、Pb、Zn在PM2.5中高度富集。在煤中,As大部分以As5+存在,少部分以As3+存在,As5+占总砷的71%。经过高温燃烧,As富集在飞灰和细颗粒中。在底灰、飞灰和PM2.5中,As主要以As5+存在,相对含量分别为总As的84%、81%和87%。In order to study the release of trace elements from small coal-fired boiler and their impact on the environment, V, Cr, Mn, Co, Ni, Cu, Zn, As, and Pb in the coal, fly ash, bottom ash and PMz.5 flue gas particles were analyzed by Synchrotron Radiation X-ray Fluorescence （SR-XRF） and valence of arsenic were measured by K-edge X-ray Absorption Near Edge Spectrum （XANES）. Characteristics of migration and accumulation of the trace elements in the combustion process were studied based on the elemental concentrations in the samples. The results showed that V was depleted in fly ash and enriched in bottom ash. Mo and Co were depleted in bottom ash and enriched in fly ash. Cr, Ni, As, Cu, Pb, and Zn in the bottom ash and fly ash were in enrichment state. As, Cu, Zn, and Pb were significantly enriched in PM2.5. The arsenic in coal was mainly As^5＋ with small was amount of As^3＋. During the combustion, As was enriched in PM2.5 and fly ash. The As^5＋, as a major speciation of As, was about 84%, 81%, and 87% in bottom ash, fly ash, and PM2.5, respectively.

关 键 词：煤炭燃烧 形态 砷 SR—XRF XANES 

分 类 号：O434.19[机械工程—光学工程] X502[理学—光学]