Size distributions of PM, carbons and PAHs emitted from a generator using blended fuels containing water.

This investigation studied the size distributions of particulate matter (PM), particulate carbon, and polycyclic aromatic hydrocarbons (PAHs) that are emitted from a generator that is fueled by diesel that is blended with waste-edible-oil-biodiesel and water-containing acetone. PM samples were collected using a micro-orifice uniform deposit impactor (MOUDI) and a Nano-MOUDI (with aerodynamic diameters of 0.01-18 µm). The results reveal that waste-edible biodiesel blended with water-containing acetone (W5WA3 or W20WA3) at a load of 3 kW emitted lower ΣPM, ΣPM-EC, ΣPM-OC, ΣT-PAHs or ΣT-BaPeq concentrations than did D100, in all 13 particle size ranges, and these reductions of emissions of submicron particles exceeded 85%. Furthermore, W20WA3 emitted significantly lower concentrations of Total-PAHs and Total-BaPeq in four nano/ultrafine particle size ranges. Therefore, water-containing acetone biodieselhols can be utilized as alternatives to petroleum diesel as fuel to reduce the dangers to human health that are posed by emissions from diesel engines.

Emission reduction of NOx, PM, PM-carbon, and PAHs from a generator fuelled by biodieselhols.

This investigation examines the particulate matter (PM), particulate carbon, polycyclic aromatic hydrocarbons (PAHs), and nitrogen oxides (NOx) emitted from a generator fueled by petroleum diesel blended with waste-edible-oil-biodiesel and water-containing acetone. Experimental results show that using biodieselhols with water-containing (or pure) acetone as the fuel of generator, in comparison to using petroleum diesel, significantly reduces PM emission; roughly, this reduction increased as percentage of water-containing acetone increased. When the percentages of waste-edible-oil-biodiesel were ≤ 5 vol%, adding pure or water-containing acetone (1-3 vol%) to biodieselhols generated emission reductions of NOx, PM, particle-bound organic carbon (OC), total-PAHs, and total-BaPeq. Consequently, using water-containing acetone biodieselhols as an alternative generator fuel is feasible and helps recycle and reuse waste solvents containing water-containing acetone.

Emissions from a generator fueled by blends of diesel, biodiesel, acetone, and isopropyl alcohol: analyses of emitted PM, particulate carbon, and PAHs.

Biodiesel is one of alternative energies that have been extensively discussed and studied. This research investigates the characteristics of particulate matter (PM), particulate carbon, and polycyclic aromatic hydrocarbons (PAHs) emitted from a generator fueled by waste-edible-oil-biodiesel with acetone and isopropyl alcohol (IPA) addition. The tested biodieselhols consisted of pure diesel oil (D100) with 1-3 vol.% pure acetone (denoted as A), 1-70 vol.% waste-edible-oil-biodiesel (denoted as W), and 1 vol.% pure isopropyl alcohol (the stabilizer, denoted as P). The results show that in comparison to W1D99, W3D97, W5D95, W10D90, and W20D80, the use of biodieselhols achieved additional reduction of PM and particulate organic carbon (OC) emission, and such reduction increased as the addition percentage of pure acetone increased. Regardless of the percentages of added waste-edible-oil-biodiesel, acetone, and isopropyl alcohol, the use of biodieselhol in place of D100 could reduce the emissions of Total-PAHs (by 6.13-42.5% (average = 24.1%)) and Total-BaPeq (by 16.6-74.8% (average = 53.2%)) from the diesel engine generator. Accordingly, the W/D blended fuels (W<20 vol.%) containing acetone (1-3 vol.%) and isopropyl alcohol (1 vol.%) are a potential alternative fuel for diesel engine generators because they substantially reduce emissions of PM, particulate OC, Total-PAHs, and Total-BaPeq.

Use of a highly sensitive recombinant hepatoma cell method to determine dioxin concentrations in samples of fish and crab from a hotspot area.

A new and easy fast-screening test (the Ad-DR (adenoviral vector-dioxin response) bioassay) for dioxins in biological samples from highly dioxin-contaminated areas was developed. The aryl-hydrocarbon-receptor (AhR) reporter system was utilized to transport a dioxin-responsive-element (DRE) via an adenovirus vector into rat hepatoma (H4IIE) cells before each experiment; these DRE-H4IIE cells were utilized in the Ad-DR bioassay. Biological extracts were simultaneously analyzed by the Ad-DR bioassay and high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). A good correlation was found between the results of the HRGC/HRMS assay and those of the Ad-DR bioassay (R(2) = 0.920, p < 0.001). The bio-analytical equivalent (BEQ) value found in fish or crab caught in the abandoned pentachlorophenol plant (AP) was extremely high compared with the BEQ in fish or crab caught in two rivers nearby this abandoned plant. Dioxins were more heavily bioaccumulated in fish viscera than in fish muscles or in the whole fish. Two-way analysis of variance tests identified the significant effects of fish collection site, fish or crab tissue sample and the interaction between them on dioxin levels in the tissues of these aquatic animals. In conclusion, the Ad-DR bioassay is a useful tool to determine dioxin levels in samples of fish and crab. Compared with fish tissues, where a sample is taken (in the PCP plant or nearby rivers) is the most important factor to determine bioaccumulation of dioxins in fish.

An improved AhR reporter gene assay for analyzing dioxins in soil, sediment and fish.

Our goal was to develop a fast-screening bioassay to determine dioxin levels in the environmental and biological samples from dioxin-contaminated areas. Our original dioxin-responsive-element (DRE)-driven luciferase bioassay (using Huh7-DRE-Luc cells) was modified by reducing the incubation temperature of the cell culture from 37 to 35°C and by adding phorbol-12-myristate-13-acetate, and the modified bioassay was used to examine samples from soil, sediment, and fish. The results of this bioassay were shown to be significantly related to those of the high-resolution gas chromatography/high-resolution mass spectrometry assay of dioxins. The correlative equation was: log (PCDD/Fs I-TEQs) = 1.19 × log (BEQs) - 1.15 with R(2) = 0.95 (p < 0.001).

Vertical and diurnal characterization of volatile organic compounds in ambient air in urban areas.

More than half of the world's population lives in cities, and their populations are rapidly increasing. Information on vertical and diurnal characterizations of volatile organic compounds (VOCs) in urban areas with heavy ambient air pollution can help further understand the impact of ambient VOCs on the local urban environment. This study characterized vertical and diurnal variations in VOCs at 2, 13, 32, 58, and 111 m during four daily time periods (7:00 to 9:00 a.m., 12:00 to 2:00 p.m., 5:00 to 7:00 p.m., and 11:00 p.m. to 1:00 a.m.) at the upwind of a high-rise building in downtown, Kaohsiung City, Taiwan. The study used gas chromatography-mass spectrometry to analyze air samples collected by silica-coated canisters. The vertical distributions of ambient VOC profiles showed that VOCs tended to decrease at greater heights. However, VOC levels were found to be higher at 13 m than at ground level at midnight from 11:00 p.m. to 1:00 a.m. and higher at 32 than 13 m between 7:00 and 9:00 a.m. These observations suggest that vertical dispersion and dilution of airborne pollutants could be jointly affected by local meteorological conditions and the proximity of pollution sources. The maximum concentration of VOCs was recorded during the morning rush hours from 7:00 to 9:00 a.m., followed by rush hours from 5:00 to 7:00 p.m., hours from 12:00 to 2:00 p.m., and hours from 11:00 p.m. to 1:00 a.m., indicating that the most VOC compounds in urban air originate from traffic and transportation emissions. The benzene-toluene-ethyl benzene-xylene (BTEX) source analysis shows that BTEX at all heights were mostly associated with vehicle transportation activities on the ground.

High estrogen concentrations in receiving river discharge from a concentrated livestock feedlot.

Environmental estrogenic chemicals interrupt endocrine systems and generate reproductive abnormalities in wildlife, especially natural and synthetic estrogenic steroid hormones such as 17beta-estradiol (E2), estrone (E1), estriol (E3), 17alpha-ethynylestradiol (EE2), and diethylstilbestrol (DES). Concentrated animal feedlot operations (CAFOs) are of particular concern since large amounts of naturally excreted estrogens are discharged into aquatic environments. This study investigated E2, E1, E3, EE2, and DES with high performance liquid chromatography/tandem mass (HPLC-MS/MS) analyses along Wulo Creek in southern Taiwan, near a concentrated livestock feedlot containing 1,030,000 broiler chickens, 934,000 laying hens, 85,000 pigs, and 1500 cattle. Sampling was performed from December 2008 to May 2009, in which 54 samples were collected. Experimental results indicate that concentrations of EE2 were lower than the limit of detection (LOD), and concentrations of DES were only detected twice. Concentrations ranged from 7.4 to 1267 ng/L for E1, from not detected (ND) to 313.6 ng/L for E2, and from ND to 210 ng/L for E3. E1 had the highest average mass fraction (72.2 + or - 3.6%), which was significantly higher than E3 (16.2 + or - 1.7%) and E2 (11.5 + or - 2.6%). Additionally, the mean E2 equivalent quotient (EEQ) ranged from 17.3 to 137.9 ng-E2/L. Despite having a markedly lower concentration than E1, E2 more significantly contributed (52.4 + or - 6.0%) EEQ than E1 (19.7 + or - 3.5%). Moreover, the concentrations of E2, E1, and E3 upstream were significantly higher than concentrations downstream, suggesting a high attenuation effect and fast degradation in the study water. Most concentrations in winter season were higher than those of spring season due to the low dilution effect and low microbial activity in the winter season. Based on the results of this study, we recommend further treatment of the wastewater discharge from the feedlot.

Emissions in the exhaust of fishing boats after adding viscous agents into fuel oils.

In order to avoid the illegal use of fishing boat fuel A (FBFA) by traveling diesel vehicles (TDVs) in Taiwan, alternatives that are easily distinguished from premium diesel fuel (PDF) were prepared to evaluate their suitability. Two new ingredients, pyrolysis fuel oil (PFO) and residue of desulfurization unit (RDS), were added into FBFA and formed PFO0.5 and RDS0.5, respectively. Along with FBFA, these three fuels were analyzed for their chemical and physical properties. Furthermore, they were used by three fishing boats with different sizes, output powers, and weights. The engine performances and pollutant emissions were examined and monitored. Experimental results show that there are significant differences in appearance between PDF and the two new blended fuels (PFO0.5 and RDS0.5), and thus misuse or illegal use of FBFA could be substantially reduced. The fuel consumption, which is negatively related to the heating value of fuels, is in order of FBFA

Cluster analysis for polychlorinated dibenzo-p-dioxins and dibenzofurans concentrations in southern Taiwan.

This study investigates the characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the ambient air of two municipal solid waste incinerators (MSWIs: GS and RW) and a coal-fired power plant (PW) in the Kaohsiung County (KC) area in Taiwan. The results show that the toxic equivalency (TEQ) concentration in the flue gas of GS and RW averaged 0.090 and 0.044 ng international toxic equivalents (I-TEQ)/N m3, respectively. The TEQ concentration in the flue gas of PW averaged 0.050 ng I-TEQ/N m3. All PCDD/Fs concentrations from the stack flue gas are lower than the Taiwan Environmental Protection Administration emission standard. Furthermore, the mean I-TEQ concentration in the ambient atmosphere ranged from approximately 0.019 to 0.165 pg I-TEQ/N m3, much lower than the environmental quality standards for dioxins in Japan (0.6 pg TEQ/ N m3). This work classified all sampling sites into three clusters according to k-means cluster analysis. The result shows a probable direct correlation between the GS incinerator and site C. Although the concentration from the PW plant did not exceed the emission standard, it was much higher than that in Fernández-Martínez's study. For proper environmental management of dioxins, establishing a complete emission inventory of PCDD/Fs is necessary. The government of Taiwan should particularly pay more attention to power plants to address the information shortage.

Atmospheric dry deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in the vicinity of municipal solid waste incinerators.

This study focuses on the atmospheric dry deposition flux of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of the two municipal solid waste incinerators (MSWIs) located in southern Taiwan. PCDD/Fs in ambient air were taken and analyzed for seventeen 2,3,7,8-substituted PCDD/Fs during November 2004 and July 2005. Results show that the mean concentrations of PCDD/Fs in the ambient air near MSWI-GS and MSWI-RW were 0.090 and 0.097pg I-TEQ/Nm(3), respectively. Dry deposition fluxes of total PCDD/Fs were 18.0 and 23.5pg I-TEQ/(m(2)d) in the ambient air near MSWI-GS and MSWI-RW, respectively, which were considerably higher than that measured in Guangzhou, China. Annual dry deposition fluxes of total PCDD/Fs in the ambient air near MSWI-GS and MSWI-RW were 189 and 217ng/(m(2)year), respectively, which were also much higher than dry deposition of total PCDD/Fs to the Atlantic Ocean. The results of the present study strongly suggest that exposure to PCDD/Fs in this area should be reduced. In addition, parametric sensitivity shows that dry deposition flux of PCDD/Fs is most sensitive to dry deposition velocity of the particle-phase, followed by air temperature and concentration of total suspended particulate but least sensitive to dry deposition velocity of the gas-phase.

Atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans on the soils in the vicinity of municipal solid waste incinerators.

This study focuses on the atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) on the soils in the vicinity of two municipal solid waste incinerators (MSWIs), which were located in the Gangshan (GS) and the Renwu (RW) Townships of southern Taiwan. PCDD/Fs in the soils were sampled simultaneously with those in the ambient air and analyzed for 17 2,3,7,8-substituted PCDD/Fs. The results show that the mean contents of PCDD/Fs in the soils near MSWI-GS and MSWI-RW were 2.65 and 1.20 ng I-TEQ/kg dry weight, respectively. Annual wet deposition fluxes of total PCDD/Fs were 119 and 113 ng/m(2)-year in the ambient air near MSWI-GS and MSWI-RW, respectively. The results obtained in this study are much higher than those estimated for the Atlantic Ocean, where the average wet deposition was only 45 ng/m(2)-year. The annual dry deposition fluxes accounted for 58.2 and 66.7%, respectively, indicating that dry deposition was more dominant than wet deposition in the atmospheric deposition processes. The congener profiles of 17 2,3,7,8-substituted PCDD/Fs showed that OCDD dominates in the soils. The contributions of OCDD in the soils near MSWI-GS and MSWI-RW were 73.4 and 67.1%, respectively, while they were only 41.4 and 31.2% in the atmospheric deposition, respectively. These results imply that OCDD is more persistent in the environment than other congeners. The results of the present study strongly suggest that exposure to PCDD/Fs in these areas should be reduced.

Effects of CH4 and CO on the reduction of nitric oxide to nitrogen in a discharge reactor.

Additives are often added to enhance the efficiency of NO removal. This study uses a radio frequency (rf) discharge to consider the effect of added CH4 and CO to simulated NO/N2/O2/H2O mixtures on the elevation of NO conversion and the reduction of NO into N2. The enhancement levels of NO conversion when using various additives were found to be in this order: +CH4 > +CO > no additive. NO conversion reached 99.3%, 86.2%, and 77.6% when adding CH4, CO, and without additive, respectively, at inlet additive/NO molar ratio (R) = 5 and at 120 W. Moreover, the fraction of total N atoms converted from NO into N2 (FN2) was very high, reaching 99.4% and 99.5% when adding CH4 and CO, respectively, at R = 1 and at 120 W. The better operating conditions are using CH4 as the additive at R > or = 1 and a power of > 60 W to reach a higher NO conversion with a higher FN2. However, it should be noted that this rf plasma approach is not practical at this stage because of its relative low pressure.

Ambient BTEX and MTBE in the neighborhoods of different industrial parks in Southern Taiwan.

This study assessed the concentrations of five volatile organic compounds (VOCs), including BTEX (the acronym for benzene, toluene, ethylbenzene, and xylene) and methyl tertiary-butyl ether (MTBE), in six different industrial park neighborhoods in southern Taiwan, including the Nei-Pu, Ping-Tung, Ping-Nan, Ren-Wu, Lin-Yuan and Nan-Zi industrial parks. The concentrations of MTBE and BTEX ranged from undetectable to 145.6 microg/m3. Average MTBE-BTEX ratios of Nei-Pu, Ping-Tung, Ping-Nan, Ren-Wu, Lin-Yuan and Nan-Zi were (13.4:3.6:4.7:1.0:7.4), (2.9:1.0:1.7:1.3:2.9), (3.0:1.0:2.7:1.0:2.7), (5.2:1.0:8.6:1.7:4.9), (3.1:3.1:2.8:1.0:3.3) and (4.3:1.2:3.6:1.0:3.8), respectively. Moreover, average T/B ratios in Nei-Pu, Ping-Tung, Ping-Nan, Ren-Wu, Lin-Yuan and Nan-Zi were 1.3, 1.7, 2.6, 8.6, 0.9 and 2.9, respectively. High T/B ratio (8.6) in the neighborhood of the Ren-Wu industrial park suggested that the emission of large additional sources of toluene from this industrial park, or the existence of major differences in the auxiliary fuels used. Average X/E ratios in Nei-Pu, Ping-Tung, Ping-Nan, Ren-Wu, Lin-Yuan and Nan-Zi were 7.4, 2.2, 2.7, 2.9, 3.3 and 3.8, respectively. The lower X/E ratio (2.2) in the Ping-Tung neighborhood compared to elsewhere indicates an aged air parcel. Furthermore, principal component analysis also confirmed that the dominant influences in the six different industrial park neighborhoods were related to the emissions of MTBE, benzene and toluene.

Determination of atmospheric nitrate particulate size distribution and dry deposition velocity for three distinct areas.

In this study, both atmospheric particulates and dry deposited particulates were collected at a highway intersection, coastal location and suburban area in Taichung, Taiwan for the characterization of nitrate containing particulates (NCPs) in size distribution and dynamic properties. Collected particulates were placed in contact with nitron (C20H16N4) to form distinctive products of NCPs, which were examined by a SEM. For total atmospheric particulates, the sum of NCP and non-nitrate containing particulate (NNCP), the average shape factor values are 1.69, 1.49, and 1.36 for the highway intersection, coastal area and suburban area, respectively. The calculated shape factors show no significant differences with sizes. Dry deposition fluxes and atmospheric concentrations at various size ranges were estimated. The mass distributed in fine particle range (

Dry deposition of sulfate-containing particulate at the highway intersection, coastal and suburban areas.

Sulfate-containing aerosol (SCA) dry deposition at the highway intersection, coastal location, and suburban area in Taiwan were analyzed and compared. Sampling was accomplished with a surrogate surface technique. Samples particles were coated with barium chloride (BaCl(2)) in a vacuum evaporator and then exposed to a relative humidity of 85% for 2 h to form distinctive products of SCAs. Treated samples were examined by a scanning electron microscopy. SCA dry deposition fluxes were 10.2, 4.1, 3.4 microgm(-2)s(-1) and nonsulfate-containing aerosol (NSCA) dry deposition fluxes were 23.3, 8.2, 13.5 microgm(-2)s(-1) at the highway intersection, coastal, and suburban areas. At the highway intersection, both SCA and NSCA dry deposition fluxes were much higher than those at the other two sites. The dry deposition of particles was also analyzed with a traditional technique. The number median diameters (NMDs) of SCA were 0.41, 0.82, and 1.2 mum at the highway intersection, coastal, and suburban sites, respectively. The highway intersection site had a small NMD, which showed that most sulfate-containing deposited aerosols existed in fine diameter range. The mass median diameters (MMDs) of SCA were 8.8, 19.5, and 14.9 mum at the highway intersection, coastal, and suburban sites, which were much higher than NMDs. Average numbers of SCAs in total particulate were 33%, 33%, and 22% at the highway intersection, coastal and suburban areas Most deposited particulates were nonsulfate-containing at the three sampling sites. SCAs less than 10 mum contributed 29%, 8%, and 7% to the total dry deposition at the highway intersection, coastal, and suburban areas, respectively. The contribution of fine particulate was significantly higher at the highway intersection site.

Impact of polycyclic aromatic hydrocarbon emissions from medical waste incinerators on the urban atmosphere.

In this study, polycyclic aromatic hydrocarbon (PAH) emissions from two batch-type medical waste incinerators (MWIs), one with a mechanical grate and the other with a fixed grate, both operated by a medical center, were assessed. Both MWIs shared the same air-pollution control devices (APCDs), with an electrostatic precipitator and a wet scrubber installed in series. Results show that when APCDs were used, total PAHs and total benzo[a]pyrene equivalent (total BaP(eq)) emission concentrations of both MWIs were reduced from 2220 to 1870 microg/m3 and 50 to 12.4 microg/m3, respectively. We used the Industrial Source Complex Short Term model (ISCST) to estimate the ground-level concentrations of the residential area and the traffic intersection located at the downwind side of the two MWIs. For the traffic intersection, we found both total PAHs and total BaP(eq) transported from MWIs to both studied areas were not significant. For the residential area, similar results were found when APCDs were used in MWIs. When APCDs were not included, we found that total PAHs transported from MWIs accounted for < 12%, but total BaP(eq) accounted for > 90%, of the on-site measured concentrations. These results suggest that the use of proper APCDs during incineration would significantly reduce the carcinogenic potencies associated with PAH emissions from MWIs to the residential area.

Characterization of atmospheric PM10 and related chemical species in southern Taiwan during the episode days.

The concentrations of atmospheric PM10 on days with episodes of pollution were examined at four different sampling sites (CC, DL, LY, and HK) in southern Taiwan. The related to particulates water-soluble ionic species (Na+, K+, Mg2+, Ca2+, NH4+, Cl-, NO3-, SO4(2-)), carbonaceous species (EC and OC) and metallic species (Zn, Ni, Pb, Fe, Mn, Al, Si, V) were also analyzed. On the episode days of this study, the PM10 mass concentration ranged from 155 to 210 microgm(-3), from 150 to 208 microgm(-3), from 182 to 249 microgm(-3), and from 166 to 228 microgm(-3) at CC, DL, LY, and HK, respectively. The results indicate that the dominant water-soluble species were SO4(2-), NO3-, NH4+, and Cl- at the four sampling sites on these days. Moreover, the high sulfate and nitrate conversion values (SOR and NOR) presented herein suggest that secondary formations from SO2 to SO4(2-) and from NO2 to NO3- are present in significant quantities in the atmosphere of southern Taiwan on episode days. In particular, high SOR and NOR verified that both SO4(2-) and NO3- dominated the increase of atmospheric PM10 concentration in southern Taiwan on episode days.

Emission of polycyclic aromatic hydrocarbons from animal carcass incinerators.

This study investigated two batch-type animal carcass waste incinerators, one in a hog farm (HOWI) and the other in a livestock disease control centre (LIWI). Additionally, a medical waste incinerator (MEWI) with a fixed grate for the disposal of biological medical waste was also examined. A GC/MS technique was applied to analyze the concentrations of 21 polycyclic aromatic hydrocarbons (PAHs) species in the stack flue gas, bottom ash and wet scrubber (WSB) effluent. The analytical results indicated that total-PAHs in the stack flue gas for HOWI, LIWI and MEWI were mainly in the gaseous phase. Moreover, the mean total-PAHs concentrations of the stack flue gas for HOWI and LIWI were 1.5 and 1.4 times higher than for MEWI (=391 microg/m(3)), respectively. At the most carcinogenic potencies, the results revealed that the mean BaP+BbF+DBA concentrations in the stack flue gas for HOWI and LIWI were 7.6 and 4.6 times higher than those of MEWI (=1.18 microg/m(3)), respectively. Moreover, during the outbreak of foot-and-mouth disease among pigs in southern Taiwan in 1997, emissions of total-PAHs and BaP+BbF+DBA exceeded 226.2 and 2.3 kg/day, respectively.

Characteristics of the PAH emissions from the incineration of livestock wastes with/without APCD.

This study was conducted on two batch-type livestock waste incinerators, including the one with an air-pollution control device (APCD)-one wet scrubber (WSB) and the other without APCD for the disposal of livestock wastes. The concentration and composition of 21 individual polycyclic aromatic hydrocarbons (PAHs) in the stack flue gas (gas and particle phases), bottom ash, and effluent of WSB were determined. Stack flue gas samples were collected by a PAH stack-sampling system. Twenty-one individual PAHs were analyzed by a gas chromatography/mass spectrometer (GC/MS). Due to the low combustion temperature, a remarkable and significant increase in the total-PAH concentration of emission from the stack with APCD was observed when compared with the case without APCD. Measured total-PAH emission factors were 285 and 2.86 mg/kg waste for the incineration with and without APCD, respectively, while BaP (the most carcinogenic PAH) emission factors were 0.79 and 0.12 mg/kg waste for the incineration with and without APCD. The total-PAH output/input mass ratios averaged 0.011 and 0.004 with and without APCD, respectively. The result reveals that the PAH content in the auxiliary fuel during the incinerating process could affect the emission of PAH.

Profiles of PAH emission from steel and iron industries.

In order to characterize the polycyclic aromatic hydrocarbons (PAHs) emission from steel and iron industries, this study measured the stack emission of twelve steel and iron plants in southern Taiwan to construct a set of source fingerprints. The study sampled the emissions by the USEPA's sampling method 5 with the modification of Graseby for the gas and particulate phase PAH and, then, used Hewlett-Packard 5890 gas chromatograph equipped with mass spectrometer detector to analyze the samples. The steel and iron industries are classified into three categories on the basis of auxiliary energy source: Category I uses coal as fuel, Category II uses heavy oil as fuel and Category III uses electric arc furnace. The pollution source profiles are obtained by averaging the ratios of individual PAH concentrations to the total concentration of 21 PAHs and total particulate matter measured in this study. Results of the study show that low molecular weight PAHs are predominant in gas plus particulate phase for all three categories. For particulate phase PAHs, however, the contribution of large molecular weight compounds increases. Two-ring PAHs account for the majority of the mass, varying from 84% to 92% with an average of 89%. The mass fractions of 3-, 4-, 5-, 6-ring PAHs in Category I are found to be more than those of the other two categories. The mass of Category III is dominated by 7-ring PAHs. Large (or heavy) molecular weight PAHs (HMW PAHs) are carcinogenic. Over all categories, these compounds are less than 1% of the total-PAH mass on the average. The indicatory PAHs are benz[a]anthracene, benzo[k]fluoranthene, benzo[ghi]perylene for Category I, benzo[a]pyrene, acenaphthene, acenaphthylene for Category II and coronene, pyrene, benzo[b]chrycene for Category III. The indicatory PAHs among categories are very different. Thus, dividing steel and iron industry into categories by auxiliary fuel is to increase the precision of estimation by a receptor model. Average total-PAH emission factors for coal, heavy oil and electric arc furnace were 4050 microg/kg-coal, 5750 microg/l-oil, 2620 microg/kW h, respectively. Carcinogenic benzo[a]pyrene for gas plus particulate phase was 2.0 g/kg-coal, 2.4 microg/l-oil and 1.4 microg/kW h for Category I, II and III, respectively.