75t/h燃煤锅炉汞迁移转化规律研究

通过对2台75 t/h循环流化床锅炉烟气中汞排放浓度、燃煤和其他固体副产物中的汞含量进行测试,分析了燃煤大气汞的排放因子,并建立了燃煤汞的质量平衡。结果表明:燃煤锅炉中,大部分汞主要存在于烟气和脱硫副产物中,燃烧后进入炉渣、飞灰中的汞含量较少,低于5%。燃煤汞排放去向与脱硫除尘控制技术有关,不同控制技术协同除汞的效果差异较大,而单质汞是燃煤锅炉汞污染防治的重点和难点。

STUDY ON MERCURY EMISSIONS FROM 75 t/h COAL-FIRED BOILERS

By measuring the mercury content in the flue gas,coal and other by-products of two 75 t/h circulating fluidized bed boilers,mercury emission influencing factors of coal-fueled boilers were obtained,and the mercury quantity balance was established.The results indicated that 95％ above of mercury existed in flue gas and desulphurization by-products for the coalfired boiler.Mercury existed in the cinder and fly ash normally accounting for less than 5％ of the total amount.Sink of mercury emitted from coal-fired boilers,and its removal efficiency depended on the different combined desulfurization and dust control technologies.Elemental mercury was key and difficult point in developing mercury controlling technology.