燃煤热电厂烟气超低排放改造工程实践

PRACTICE OF AN ULTRA-LOW EMISSION RETROFIT PROJECT FOR A COAL-FIRED POWER PLANT

某燃煤热电厂采用SNCR-SCR耦合脱硝+布袋除尘+湿法石灰石-石膏烟气脱硫+湿式静电除尘的组合工艺对原烟气净化设施进行改造,以实现烟气污染物的超低排放。随机抽取1个月的污染物排放数据进行分析,结果表明:SO_2排放浓度非常低,平均浓度仅为6. 32 mg/m^3,应进一步优化控制参数实现经济运行。NO_x排放浓度稳定,98. 2%的时段排放浓度<50 mg/m^3,但氨逃逸控制不理想。经过湿法脱硫和湿式静电除尘后,96%的时段粉尘排放浓度<2. 5 mg/m^3。综合分析,组合工艺是一种适合燃煤烟气超低排放改造的可靠工艺。

A coal-fired power plant adopted SNCR-SCR + bag filter + wet limestone-gypsum flue gas desulfurization + wet electrostatics precipitation technology to retrofit the original flue gas purification facilities to achieve ultra-low emission of flue gas pollutants. Through analyzing the data of one-month pollutants emission selected randomly,the results showed that the SO2 emission concentration was very low and the average concentration was only 6. 32 mg/m^3,but the control parameters should be further optimized to achieve economical operation. The NOx emission concentration was stable,and its concentration was less than 50 mg/m^3 in 98. 2% of the total monitoring period. However,ammonia escape was not controlled well. After wet desulfurization and wet electrostatic precipitation,the dust emission concentration was below 2. 5 mg/m^3 in 96% of the total monitoring period. In a word,the combined technology used in this project is a suitable process for the transformation of ultralow emission for coal-fired power plants.