基于实测的燃煤电厂汞排放特性分析与研究

为了研究某典型300 MW燃煤电厂汞排放特性,对入炉煤、炉渣、石灰石、脱硫工艺水、石膏、脱硫废水、灰中的汞进行了取样测试。并采用EPA30B和安大略法实测了不同位置烟气中汞的形态分布情况。结果表明:该机组汞排放浓度满足GB 13223—2011《火电厂大气污染物排放标准》。烟气中的汞排放比重相当大,达到89.52%,排向大气环境的汞量约为38.72μg/(k W·h)。该典型300 MW机组尾部烟气净化系统为SCR+ESP+WFGD组合,对烟气中的汞脱除效率仅为29.71%,在未加入脱汞措施的情况下汞脱除率并不高。

MERCURY EMISSION CHARACTERISTICS FROM COAL-FIRED POWER PLANTS BASED ON FIELD TESTS

Coal，slag，limestone，water in desulfurization process，gypsum，desulfurization wastewater and ash were sampled and tested in order to study mercury emission characteristics from a typical coal-fired power plant． EPA30B and Ontario-Hydro methods were applied to determine the mercury speciation of flue gas in different position． The results indicated that the mercury emission concentration of 300 MW unit met“Emission Standard of Air Pollutants for Thermal Power Plants”( GB 13223—2011) ． The mercury emission in flue gas accounted for a considerable proportion，reaching 89. 50%，and the amount of mercury emission into the atmosphere was about 38. 72 μ g / ( kW·h) ． The flue gas purification system of typical 300MW units was SCR + ESP + WFGD combined process，and the removal efficiency of mercury in flue gas was only 29. 71%，and mercury removal rate was not high without strengthen the mercury removal measures．