| Title: | Characteristics of PM and PAHs emitted from a coal-fired boiler and the efficiencies of its air pollution control devices |
| Author(s): | Chen TW; Chen JC; Liu ZS; Chi KH; Chang MB; |
| Address: | "Graduate Institute of Environmental Engineering, National Central University, Taoyuan, Taiwan. Department of Environmental Engineering and Science, Feng Chia University, Taichung, Taiwan. Department of Safety Health and Environmental Engineering, Ming Chi University of Technology, New Taipei, Taiwan. Institute of Environmental and Occupational Health Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan" |
| DOI: | 10.1080/10962247.2021.1994483 |
| ISSN/ISBN: | 2162-2906 (Electronic) 1096-2247 (Linking) |
| Abstract: | "Sampling and analysis of filterable particulate matter (FPM), FPM(2.5), condensable particulate matter (CPM), polycyclic aromatic hydrocarbons (PAHs), sulfur oxides (SO(x)), and nitrogen oxides (NO(x)) emitted from a coal-fired boiler equipped with selective catalytic reduction (SCR)+ electrostatic precipitator (ESP) + wet flue gas desulfurization (WFGD) + wet electrostatic precipitator (WESP) as air pollution control devices (APCDs) are conducted. The results show that NO(x) concentration emitted from the coal-fired boiler is 56 +/- 2.17 ppm (with the NO(x) removal efficiency of 47.2%), which does not meet the best available control technology (BACT) emission standard ( 99%. The FPM and FPM(2.5) emitted from the coal-fired boiler are 0.9 +/- 0.06 mg/Nm(3) and < 0.09 +/- 0.006 mg/Nm(3), respectively. The overall removal efficiency of FPM achieved with ESP+WFGD+WESP+MGGH is 99.98%. However, high concentration of CPM (37.4 +/- 6.3 mg/Nm(3)) is measured, which is significantly higher than FPM and FPM(2.5). The concentrations of 27 PAHs at the WESP inlet and stack are measured as 667 ng/Nm(3) and 547 ng/Nm(3), respectively while the removal efficiencies of gas- and solid-phase PAHs are 9% and 58%, respectively. The results show that APCDs adopted are not effective in removing PAHs (only 18%), and gas-phase PAHs contribute the most in the total PAH emission. In addition, the benzo(a)pyrene equivalent (BaP(eq)) concentration emitted from the stack is 28.8 ng-BaP(eq)/Nm(3), and most of it is contributed by 4-6 ring PAHs with high toxic equivalent factors (TEFs). Furthermore, the emission factors of air pollutant emitted from coal-fired boilers equipped with different combinations of APCDs are compiled and compared. The results show that except for CPM and NO(x), the emission factors of air pollutant calculated for this coal-fired boiler are lower if compared with other studies.Implications: Primary particles discharged from coal-fired processes include filterable particulate matter (FPM) and condensable particulate matter (CPM). PM(2.5) emissions would be greatly underestimated if CPM is ignored. Polycyclic aromatic hydrocarbons (PAHs) are semi-volatile organic compounds (SVOCs) formed by two or more fused benzene rings. PAHs have attracted much public attention because of toxicity and carcinogenicity. This study selects one coal-fired boiler with the best available control technology (BACT) to simultaneously measure the concentrations of PM, PAHs, and gaseous pollutants at the inlet and outlet of air pollution control devices (APCDs) to understand the efficacy of APCDs adopted and pollutant emission intensity" |
| Keywords: | *Air Pollutants/analysis *Air Pollution/prevention & control Coal/analysis Particulate Matter/analysis *Polycyclic Aromatic Hydrocarbons Power Plants; |
| Notes: | "MedlineChen, Tang-Wei Chen, Jyh-Cherng Liu, Zhen-Shu Chi, Kai-Hsien Chang, Moo Been eng Research Support, Non-U.S. Gov't 2021/10/16 J Air Waste Manag Assoc. 2022 Jan; 72(1):85-97. doi: 10.1080/10962247.2021.1994483. Epub 2021 Dec 3" |
