重庆市燃煤电厂汞排放特征及排放量  

Characteristics of Mercury Emissions from Coal-fired Power Plants in Chongqing

作　　者：张成[1,2] 张雅惠[1] 王永敏[1] 王定勇[1,2] 徐凤[3] 杨熹[3] 何秀清[3] 

机构地区：[1]西南大学资源环境学院,重庆400715 [2]重庆市农业资源与环境研究重点实验室,重庆400715 [3]重庆市固体废物管理中心,重庆401117

出　　处：《环境科学》2017年第2期495-501,共7页Environmental Science

基　　金：国家重点基础研究发展规划(973)项目(2013CB430004);重庆市环保局科技项目(2013CF101);中央高校基本科研业务费专项(XDJK2015B036)

摘　　要：以重庆市两种锅炉类型[循环流化床锅炉(CFB)和煤粉炉(PC)]的4个燃煤电厂为研究对象,分析不同规模电厂输入输出物料汞含量,探讨电厂中汞的来源和去向,研究重庆市典型燃煤电厂汞的排放特征,估算其大气汞排放量和排放因子.结果表明,4个电厂的汞主要来源为煤,入炉煤汞含量为(80.77±6.39)^(266.83±4.71)μg·kg-1.4个电厂排放的汞主要进入了固体废物,其中,CFB电厂中汞的去向主要是粉煤灰,而PC电厂汞的去向主要是脱硫石膏和粉煤灰.4个电厂的汞脱除率为72.89%~96.05%,CFB电厂高于PC电厂.4个电厂的大气汞排放因子(EF电、EF煤)分别为4.66~29.47μg·(k W·h)-1和8.55~71.77 mg·t-1,大气汞排放量为6.13~429.17 g·d-1.燃煤电厂的汞排放与煤中汞含量、锅炉类型、发电负荷、污控设备等因素有关.为控制电厂汞排放,需改善燃煤机组的能效,提高烟气净化设备的除汞效率,加强燃煤电厂的固体废物利用监管.Four typical coal-fired power plants in Chongqing, representing two different boiler types （circulating fluidized bed boiler and pulverized coal boiler）, were chosen to investigate mercury emission characteristics through a mercury mass balance method by analyzing mercury contents in all input and output raw materials in order to accurately estimate mercury emissions. The results showed coal with mercury concentrations ranging （80. 77 ± 6. 39）-（266. 83 ± 4. 71） μg·kg ^- 1 could be a significant contributor of input mercury in these four studied power plants. Most mercury output from these power plants entered into solid waste with high proportion of mercury entering the fly ash in CFB plants and entering the fly ash and desulfurization gypsum in PC plants. Mercury removal efficiencies of studied plants were in the range of 72. 89% -96. 05% , and these efficiencies in CFB plants were higher than those in PC plants. The mercury emission factors for EFelectricity and EFcoal of these four plants were 4. 66-29. 47 μg·（kW·h）^ - 1 and 8. 55-71. 77 mg·t ^- 1 , respectively. The mercury emission was also calculated to be 6. 13-429. 17 g·d^ - 1 . Mercury emissions from coal-fired power plants were associated with the content of mercury in coal, boiler type, generation load, pollution control equipment, and so on. To control the mercury emissions, more attention should be paid to improving the generation load, increasing the mercury removal efficiency of flue gas cleaning equipment, and strengthening the supervision of solid waste re-utilization.

关 键 词：燃煤电厂 汞排放 排放因子 循环流化床锅炉 煤粉炉 

分 类 号：X511[环境科学与工程—环境工程]