燃煤电厂除尘设施对烟气中微量元素的减排特性分析

Analysis on Reduction of Trace Elements in Flue Gas by Dust Removing Facilities in Coal-fired Power Plants

对我国9家典型燃煤发电机组除尘设施前后烟气中Hg、F、Cl、Pb的形态和浓度进行现场测试,研究除尘设施对燃煤烟气中微量元素的形态转化及协同减排作用。结果表明:除尘设施对烟气中Hg、F、Cl、Pb的影响主要体现在对颗粒态污染物的协同减排上。燃烧方式、煤质、除尘器形式、有无选择性催化还原对除尘设施的脱汞效率影响很大;除尘设施前烟气中氟、氯以HF、HCl为主,除尘设施对其浓度的影响不明显,对烟气中总F、Cl的脱除效率较低。除尘设施前烟气中铅以Pb P为主,因而除尘设施对烟气中总Pb的脱除效果较好。

The species distribution and content of Hg, F, Cl, Pb in flue gas were measured before and after the dust removing facilities of nine typical coal-fired power plants, and the effect of dust removing facilities on their species distribution and concentration were investigated. The results indicate that the dust removing facilities have remarkable effects on removal of particulate trace elements. The combustion type, coal properties, dust removing facility type and SCR have important influence on mercury removal. The halogens in flue gas mainly exist in the form of HF and HCl, and dust removing facilities have little effect on HF and HCl, so The halogens removal efficiency is lower. The lead in flue gas mainly exists in the form of PbP, so the lead removal efficiency is higher.