燃煤电厂细颗粒物中微量元素排放影响研究  

Effects of Trace Element Emission in Particulate Matter from Coal-fired Power Plants

作　　者：王润芳 姚为方 马大卫 邢琛 华雪莹 徐鹏 周健 陈国宏 汤泉[3] WANG Runfang;YAO Weifang;MA Dawei;XING Chen;HUA Xueying;XU Peng;ZHOU Jian;CHEN Guohong;TANG Quan(Anhui Xinli Power Technology Consulting Co.,Ltd.,Hefei 230026,China;State Grid Anhui Electric Power Research Institute,Hefei 230601,China;School of Life Sciences,Anhui University,Hefei 230601,China)

机构地区：[1]安徽新力电业科技咨询有限责任公司,合肥230026 [2]国网安徽省电力有限公司电力科学研究院,合肥230601 [3]安徽大学生命科学学院,合肥230601

出　　处：《科技和产业》2023年第9期177-183,共7页Science Technology and Industry

基　　金：国家自然科学基金(42072200);安徽新力电业科技项目(2020咨-KJ-03)。

摘　　要：燃煤电厂排放颗粒物中的各种微量元素引起公众的广泛关注。为探究燃煤电厂排放颗粒物中微量元素含量及主要环保设备对元素排放的影响,通过现场试验、文献调研、理化分析等方法,对安徽省一台600 MW超低排放、超临界机组湿法脱硫装置(WFGD)和湿式电除尘装置(WESP)排放细颗粒物中Cr、As、Se、Cd、Pb、Hg元素分布及排放特征进行综合研究。结果表明:燃煤机组排放PM_1、PM_(1~2.5)和PM_(2.5~10)的细颗粒物浓度分别为0.85、0.18和0.02 mg/m~3,WFGD对PM_(2.5~10)的脱除效率达到95%以上,WESP对粒径小于2.5μm细颗粒物的去除效率优于WFGD。WFGD入口处PM_(10)中Cr、As、Se、Cd、Pb、Hg的质量浓度分别为22.8、0.2、28.9、27.7、7.3、2.4μg/m~3,各元素质量浓度在不同分级颗粒物中的分布规律均呈现随着粒径增大而降低的趋势。颗粒物在经过WFGD后,Se元素质量浓度下降70%,Cr元素质量浓度增加466%,Hg和Pb元素质量浓度增长325%和205%,Cd和As增长101%和113%,微量元素主要富集在细颗粒物中。WESP出口处PM_(10)中Cr、As、Se、Cd、Pb、Hg的质量浓度分别为8.3、0.2、8.9、8.2、3.5、1.0μg/m~3,颗粒物中有害微量元素呈下降趋势,其中Se元素质量浓度变化较小,其他5种元素质量浓度均下降约50%。Human-induced harmful trace elements have attracted public attention.Particulate matter emitted by coal-fired power plants contains various trace elements.The distribution and emission of Cr,As,Se,Cd,Pb and Hg in the particulates emitted by wet flue gas desulfurization(WFGD)and wet electro staticpreci pitator(WESP)of a 600 MW ultra-low critical unit in Anhui Province were comprehensively studied,literature research,and physical and chemical analysis.The results show that the particulate matter concentrations of PM 1,PM 1~2.5 and PM 2.5~10 emitted by coal-fired units were 0.85,0.18and 0.02 mg/m 3,respectively.The removal efficiency of WFGD for PM 2.5~10 was over 95%,and WESP for particle size smaller than the removal efficiency of 2.5μm fine particles is better than WFGD.The mass concentrations of Cr,As,Se,Cd,Pb and Hg in PM 10 at the inlet of WFGD were 22.8,0.2,28.9,27.7,7.3 and 2.4μg/m 3,respectively.The distribution law of the mass concentration of each element in different graded particles showed a decreasing trend with the increase of particle size.After the particles passed through WFGD,the Se element mass concentration decreased by 70%.The mass concentration of Cr element increased by 466%.The mass concentrations of Hg and Pb elements increased by 325%and 205%,respectively.Cd and As increased by 101%and 113%,respectively.WFGD increases the mass concentration of trace elements in particulates,which are mainly concentrated in fine particulates.The mass concentrations of Cr,As,Se,Cd,Pb and Hg in PM 10 at the outlet of WESP were 8.3,0.2,8.9,8.2,3.5 and 1.0μg/m 3,respectively.The mass concentration of Se element changed little,and the mass concentrations of the other five elements all decreased by about 50%.

关 键 词：燃煤电厂 湿法脱硫装置(WFGD) 湿式电除尘装置(WESP) 细颗粒物 微量元素 

分 类 号：X513[环境科学与工程—环境工程]