燃煤机组SO_3迁移规律及排放特性试验

SO_3 migration and emission characteristics of coal-fired power units

针对燃煤电厂SO_3排放现状,对国内多个典型燃煤机组(包括达标排放机组和超低排放机组)各污染物控制设备前后的SO_3质量浓度进行现场测试,并分析了国内典型燃煤机组的SO_3迁移规律。结果表明:达标排放机组的SO_3排放质量浓度普遍高于5 mg/m^3,而超低排放机组的SO_3排放质量浓度大多低于5 mg/m^3;燃煤机组SO_3迁移规律为烟气经选择性催化还原(SCR)脱硝装置后SO_3质量浓度明显增加,而经后续的电除尘装置、脱硫装置、低低温电除尘装置及湿电除尘装置后SO_3均得到有效脱除。

Against the current situation of SO3 emission from coal-fired power plants,the mass concentration SO3 in front and behind each pollutant control equipment of several domestic typical coal-fired units,including the ultra low emissions units and the units of which the emission satisfies the standard's requirement(short for discharge units),was tested in site.The results show that,the mass concentration of SO3 emitted from most of the discharge units is higher than 5 mg/m3,and that from a majority ultra low emission units is below 5 mg/m3.Moreover,the migration of SO3 in flue gas can be described as follows:after the flue gas flows through the SCR denitration equipment,the SO3's mass concentration increases,it can be effectively removed by the subsequent ESP equipment,desulfuration equipment,low temperature ESP device and WESP device.