燃煤火电厂汞排放因子测试设计及案例分析

在火电厂锅炉煤的燃烧中,汞的迁移是个复杂的过程.在炉内高温下,几乎所有的汞以气态形式停留于烟气中,随着烟气温度的降低,汞被再分配到粉煤灰、炉渣和空气中.采用测试和衡算的方法,对火电厂汞排放因子进行测试和分析.结果表明:汞的迁移分配与煤中汞的赋存量、粉煤灰中可燃物碳的含量及烟气温度相关.煤燃烧后,进入粉煤灰中的汞占煤中汞含量的12.7%～31.3%,进入炉渣中的汞占0.9%～12.8%,大部分汞排入大气中,占67.8%～82.2%.

Study on Mercury Emission Factors for Coal-Fired Power Plants

Mercury transportation is a complex process during coal combustion in coal-fired power plants. The study works on emission factors of mercury from power plants by way of testing and mass balancing. It proves that mercury transportation and distribution are related to the factors such as mercury content in coal, combustible carbon content in ash and the temperature of flue gas. After coal combustion, about 12.7% to 31.3% of mercury is redistributed into ash, 0.9% to 12.8% into slag and mostly into the atmosphere, taking a percentage of about 67.8% to 82.2%.