Characteristics of Emission of Mercury With Fume From Coal-Burning Power Plant

To better understand characteristics of the system of emission of mercury with fume from coal-burning power plants, seven coal-burning power plants located in five different regions in Jiangsu Province were selected for in-situ sampling according to the USA EPA 30B approach for analysis of effects of mercury concentration in coal, generating units capacity and emission control facilities on the emission of mercury with fume. Results show that Hg concentration in the fume is not very much related to Hg content in the coal, but in significant negative exponential relation to the generating units capacity (P<0.01). It seems that the use of circulating fluidized bed boilers coupled with electrostatic precipitators is very efficient in removing mercury from the fume emitted from coal-burning power plants, reaching up to 98.9% in mercury removal efficiency, much higher than the efficiency of the use of the pulverized coal furnaces couples with electrostatic precipitators and lime-gypsum wet desulfurization equipment (67.5%-81.6%). It is, therefore, concluded that the technology of circulating fluidized bed boiler coupled with electrostatic precipitator is more efficient in removing mercury in fume emitted from coal-burning power plants.