Characteristics of Fine Particulate Matter and Polycyclic Aromatic Hydrocarbons Emitted from Coal Combustion Processes

Abstract

Characteristics and emission factors of condensable particulate matter (CPM) and filterable particulate matter (FPM2.5) and polycyclic aromatic hydrocarbons (PAHs) (16 U.S. EPA PAHs and 15 + 1 EU PAHs) emitted from a coal-fired power plant (plant A) and a coal-fired boiler (plant B) in Taiwan were investigated via stack samplings. Removal efficiencies of CPM, FPM2.5, and PAHs achieved with baghouse (BH) + seawater flue gas desulfurization (SWFGD) were also evaluated for plant A. Results indicate that CPM concentrations measured in plants A and B are 12.7 ± 1.44 and 28.0 ± 6.32 mg/Nm3, respectively, which are significantly higher than FPM2.5 concentrations measured in two plants. The CMP/FPM ratios measured in plants A and B are 12.7 ± 1.44 and 28.0 ± 6.32, respectively. The organic content is the major contributor to CPM collected from plant A (90 ± 3.7%), while the inorganic content contributes 93 ± 2.4% of CPM collected from plant B. Furthermore, different compositions of soluble ion are found in CPM/FPM collected from the stacks of plants A and B. This difference might be attributed to different coal used, varying combustion efficiencies, and different removal efficiencies of organic and inorganic contents achieved with different air pollution control devices (APCDs) with different operating temperatures in plants A and B. The average PAH concentrations measured at stacks of plants A and B are 28.4 and 43.4 μg/Nm3, respectively. Gaseous PAHs predominate in terms of both mass and toxic equivalency (TEQ) concentrations, acounting for 99.5 and 96.0%, respectively. The 15 + 1 EU PAHs contribute 99.0 and 99.99% to total TEQ of gaseous and particulate PAHs, respectively. The removal efficiency of CPM achieved with BH and SWFGD of plant A is 38.3%, which is significantly lower than that of FPM2.5 (99.8%) and PM (99.9%). The PAH removal efficiency achieved with APCDs in plant A increases as the ring number increases. The overall PAH removal efficiencies achieved with the APCDs of plant A are 89.8 and 94.3% based on mass and TEQ concentrations, respectively.

Emission of PM2.5-Bound Polycyclic Aromatic Hydrocarbons from Biomass and Coal Combustion in China

“…Those boilers were all equipped with air pollution control devices (APCDs). The previously reported emission factors of total PAH species (including gas phase and particulate phase) for PC boilers are very low, in the range of 0.002 to 0.6 mg/kg [20,[45][46][47]. Our ΣPAHs emission factors from PC boilers for the particulate phase fall in the range of those values.…”

PM10 and PM2.5 Qualitative Source Apportionment Using Selective Wind Direction Sampling in a Port-Industrial Area in Civitavecchia, Italy

“…Generally, these two pollutants are related to diesel vehicular emissions [46][47][48][49][50][51][52] whereas the petrol vehicle emissions are characterized by B[a]P and dibenzo[ah]anthracene emissions [53][54][55][56][57]. For coal combustion, the PAHs profiles are generally characterized by a high presence of fluoranthene, pyrene, phenanthrene and anthracene, to which the chrysene and the isomer of benzo[k]fluorantene are added [58][59][60][61]. Regarding marine emissions, for ships at the port both in mooring and maneuvering, the PAHs fingerprint is represented by naphthalene, phenanthrene, pyrene, fluorene, followed by acenaphthylene and acenaphthalene [62][63][64][65].…”

Non-Negligible Stack Emissions of Noncriteria Air Pollutants from Coal-Fired Power Plants in China: Condensable Particulate Matter and Sulfur Trioxide

“…In terms of CPM, nonfilterable particles exist in the vapor phase before being discharged from stack and condense to fine particulate substances (aerodynamic diameter less than 2.5 μm) after cooling in the plume. ,− In fact, total particulate matter (TPM) emissions should be the sum of FPM and CPM. Several previous studies stated that CPM emissions represented the predominant contributors to TPM emissions based on field tests; − final TPM emissions will be severely underestimated if CPM is not considered. Corio and Sherwell pointed out that the proportion of CPM in PM 10 emitted from coal-fired boilers was 76%, and the results conducted by Zheng et al showed that CPM accounted for 76.73% in TPM.…”