燃用高灰高硫煤电厂的汞排放研究

考察了燃用高灰(38.49%)高硫(3.47%)煤，并安装了选择性催化还原烟气脱硝(SCR)、石灰石-石膏湿法脱硫(WFGD)和静电除尘器(ESP)设施电厂的汞排放状况，以及烟气污染控制技术对烟气中汞形态和浓度的影响。结果表明，煤中灰分比例高导致锅炉出口烟气中颗粒汞(Hg^P)的比例明显高于气态汞；静电除尘器的协同脱汞效率高达80.56%，这主要由颗粒汞在烟气汞中所占比例决定；选择性催化还原烟气脱硝装置对烟气中汞形态和浓度的影响不明显；而石灰石-石膏湿法脱硫设施对烟气中汞的协同脱除效率仅为28.49%。

Study on Mercury Emissions from a Power Plant Burning High Ash and High Sulfur Coal

The mercury emission status of a power plant burning high-sulfur (3.47%) and high-ash (38.49%) coal and installed with pollutant emission control devices including selective catalytic reduction (SCR), wet-flue gas desulphurization (WFGD) and electrostatic precipitator (ESP) was investigated, and the effects of pollution control technologies on mercury forms and concentrations in flue gas discussed. The results showed that the particulate mercury proportion was higher than gaseous mercury due to high ash in the coal. The mercury removal efficiency could reach up to 80.56% after flue gas passing through ESP, depending on the particulate mercury proportion in the flue gas. There was no significant effect of SCR on mercury forms and concentrations in the flue gas. In comparison, WFGD could remove only 28.49% of mercury.