Concentration of Filterable and Condensable PM from Coal, Oil and LNG-fired Power Plants

This study investigated the emission characteristics of filterable particulate matter (FPM) and condensable particulate matter (CPM) emitted from coal, oil, and LNG-fired power plants. FPM and CPM were measured in two power plants for each fuel type. FPM was measured using a cascade impactor (KSI 23210) in particle size categories of PMtotal, >PM10, PM2.5-10, and PM2.5, CPM was measured using a dry impinger (U.S EPA method 202) that separates inorganic and organic components. The average FPM concentration of coal, oil, and LNG-fired power plants were 1.86 mg/m(3) (@O-2 6%), 3.05 mg/m(3) (@O-2 4%), and 0.05 mg/m(3) (@O-2 15%), respectively. The lowest FPM concentration was measured in LNG-fired gas turbines. This indicates that the emission limits at heavy oil-fired power plants are higher than those at coal-fired power plants and each power plant must adhere to the set emission limits. The particle size of FPM emitted from power plants varied depending on the fuel type. While the ratio of fine particles (FPM2.5/FPM) was approximately 0.95 for plants fueled by coal or heavy oil, it was approximately 0.36 for LNG-fired gas turbines. This difference can be attributed to the presence of electrostatic precipitator and wet-scrubber in coal and heavy oil-fired power plants, which remove a majority of large particles. In contrast, most of the particles generated in LNG-fired gas turbines are emitted as is due to the absence of particle collectors, since LNG-fired gas turbines have lower FPM concentrations. The average CPM concentration of coal, heavy oil-fired power plants and LNG-fired gas turbines were 2.55 mg/ m(3) (@O-2 6%), 14.20 mg/m(3) (@O2 4%), and 0.50 mg/m(3) (@O-2 15%), respectively. The CPM concentrations were higher than the FPM concentrations. By fuel type, coal, heavy oil, and LNG-fired power plant shewed CPM concentration that were 1.4, 4.6, and 10.6 times higher FPM concentrations. CPM in emissions from coal and heavy oil-fired power plants exhibited significantly higher inorganic fractions, approximately 7 and 88 times higher, respectively, while LNG-fired gas turbines had a similar ratio of inorganic and organic components. The FPM and CPM emission factors (controlled) for coal-fired power plants were 0.0172 kg/ ton and 0.0228 kg/ton, respectively, consistent with other research. The FPM and CPM emission factors (controlled) for heavy oilfired power plants were 0.0362 kg/kL and 0.1682 kg/kL, respectively with the FPM emission factor being inconsistent with that of other research findings. Lastly, the FPM and CPM emission factor (uncontrolled) for LNG-fired gas turbines were 0.00256 kg/km(3) and 0.01773 kg/km(3), respectively, which is lower than that of the AP-42 data but consistent with more recent research data. The emission characteristics of FPM from power plants vary according to emission facility regulations such as emission limits and maximum permissible levels. The emission characteristics of CPM are influenced by factors such as exhaust gas temperature and precursors, including water-soluble SO2, NH3 gas and volatile organic compounds. However, a correlation equation between various exhaust gas conditions and CPM has not been proposed yet. Therefore, further research is necessary to investigate the concentration, chemical components, and exhaust gas conditions of CPM.