PAHs Emission Characteristics and Assessment from the Coal Combustion Process in the Large Capacity Power Plant Boilers

摘要

Many studies have demonstrated an association between exposure to ambient Polycyclic Aromatic Hydrocarbons (PAHs) and some serious diseases, such as cancer, malformation and mutation. PAHs is thought as a carcinogenic and mutagenic compound to human health. Coal-fired power plant industry plays an important role in the observed PAHs emission process. However, the PAHs emission characteristic and environment impact in coal-fired power plant is still not fully clarified. In this study, the PAHs distribution characteristic of the flue gas and fly ash emitted from electrostatic precipitator in two coal-fired power plant boilers with the steam capacity 1000t/h and 2000t/h have been studied in China based on USEPA method 0023(sampling part). PAHs concentrations and PAHs emission factors were determined. And the correlation between PAHs emission and the steam capacity of the power plant boiler was discussed. In addition, the PAHs removal effects of air pollution control devices were also included. According to the measured PAHs emission data and the report of China statistical year book, the PAHs emission assessment from the coal combustion process in the large capacity co-fired power plant boilers have been done. Though the PAHs emission value in the large capacity power plant were present within recommended emission limits of energy production, the problem of PAHs emission in large capacity coal-fired power plant shouldn't be ignored due to the huge amounts and long-range transport in soil, water and ambient air.