1. School of Energy and Power Engineering,North China Electric Power University,Baoding　 071003,China;2. North China Electric Power Research Institute Co. ,Ltd. ,Beijing　 100045,China

对安装有电袋复合除尘器(HPC)和湿法脱硫装置(WFGD)的320 MW燃煤电厂,采用EPA method 29对脱硫后烟气重金属浓度进行测试,同时测定了其他燃煤产物中重金属浓度,分析了除尘和脱硫系统中重金属富集特性,研究了HPC和WFGD对烟气中重金属的脱除作用,比较了不同负荷下HPC和WFGD协同控制作用。结果表明:As,Pb,Cr在袋区灰富集程度更大,电区灰中分布总量更多;袋区能有效捕集烟气中气态汞,Hg富集系数高达1.01。脱硫系统中Hg,As,Pb,Cr均向石膏大规模富集。HPC对Hg的脱除率达到50%,As,Pb,Cr平均脱除率为85%。WFGD对As,Pb,Cr平均脱除率为82%,对Hg的脱除率达到91%。在75%和100%负荷下,烟气中90%以上的Hg,As,Pb,Cr均可被HPC+WFGD协同捕获,HPC在对多种重金属排放控制中起主要作用,且低负荷下减排任务更重。

Taking a 320 MW unit equipped with hybrid particulate collector ( HPC) and wet flue gas desulfurization (WFGD) as an example,the content of Hg,As,Pb,Cr in flue gas after WFGD was measured by applying the US En- vironment Protection Agency (EPA) method 29,coal and other combustion products were also sampled. The heavy metals enrichment characteristics and removal efficiency of HPC and WFGD were analyzed,and the collaborative con- trol of HPC and WFGD on heavy metals emission under different boiler loads were also compared. The results show that As,Pb,Cr are obviously enriched in fabric filtration ash,but distributed more in electrostatic precipitation ash. Fabric filtration can effectively capture the gaseous mercury in flue gas,the relative enrichment factor of Hg is 1. 01. Hg,As,Pb,Cr in WFGD system all migrate to gypsum in a large scale. The average removal efficiency of As,Pb,Cr by HPC and WFGD are 85% and 82% respectively. The total Hg removal efficiency of HPC is 50% ,while that of WFGD is 91% . Under the load of 75% and 100% ,over 90% of Hg,As,Pb,Cr can be removed by HPC+WFGD. HPC plays a major role in heavy metals emission control,especially under low boiler load.

国家自然科学基金资助项目(51276064)；

Wang Chunbo,Shi Yanhong,Wu Huacheng,et al. Research on collaborative control of heavy metals discharge from coal combustion by hy- brid particulate collector and wet flue gas desulphurization[J]. Journal of China Coal Society,2016,41(7):1833-1840.