Toxic Pollutants Emitted from Heavy Diesel Engine

Transcription

1 Toxic Pollutants Emitted from Heavy Diesel Engine Lin-Chi Wang Department of Chemical and Materials Engineering Super Micro Mass Research and Technology Center Cheng Shiu University, Taiwan

2 Introduction Motor vehicles have long been recognized as one of the most significant sources of air pollution in urban areas, and diesel particulate matter (PM) was identified as a toxic air contaminant, especially those with diameters less than 2.5 μm. The vicinity to the ambient environments could make vehicles important PM 2.5 emission sources.

3 Wenger et al. (28) investigated AhR mediated activity of exhaust generated by a heavy-duty diesel engine. AhR agonists were quantified using the DR-CALUX reporter gene assay. They found that the nine PAHs and the 17 2,3,7,8-PCDD/Fs only contributed.6 1.6% to the total agonist concentration.

4 For further investigating the characteristics of the toxic pollutants emitted from heavy diesel engine, in this study, an analytical method was developed to simultaneously measure several pollutants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) from one exhaust sample.

5 Target pollutants PCBs PBDEs, structurally similar to PCDD/Fs and PCBs, are used as flame retardants in furniture, electronic goods and other consumer items. PBDEs 5

6 Due to health risks, the commercial penta-bde, octa-bde and deca-bde mixtures were banned within the European Union. Many studies have reported that environmentally ubiquitous PBDEs are mainly the result of using PBDEcontaining products indoors.

7 Our recent studies concerning incinerators and metallurgical processes suggested that PBDEs could form or survive from the PBDE-contaminated feeding materials in the combustion system (Wang et al., 21a; Wang et al., 21b). 7

8 In this study Testing was conducted on a heavy-duty diesel engine with no aftertreatment devices to establish a baseline measurement (denoted as B1). The engine was then subjected to two additional test cycles, one with the diesel oxidation catalyst (DOC) (B1+DOC) and another fueled with lower sulfur fuel (<1 ppm) (S1).

9 Materials and Methods Testing Facility Particulate and gaseous phase pollutants were collected from the secondary dilution tunnel with a sampling train that consisted of precleaned filter, PUF and XAD-2. The diesel engine (Cummins, type B5.9-16): six cylinders, turbocharged with direct fuel injection, total displacement volume of 588 c.c. The PM filters was size-separated collecting the particle and diameters collected less from than primary 2.5 dilution μm were all tunnel combined with a as micro-orifice a composition uniform sample deposit for impactor further (MOUDI) chemical and a analyses. Nano-MOUDI.

10 Emissions were determined over a cold start cycle followed by three to five hot starts of the FTP 32 testing cycles, with each cycle separated by the required 2-min soak period.

11 Analytical Procedures PAHs PCBs PBDEs PCDD/Fs

12 Instrumental Analysis HRGC (Hewlett Packard 697 Series gas chromatograph) HRMS (Micromass Autospec Ultima)

13 Results and Discussion Gaseous regulated pollutants HC CO CO 2 NOx PM Start mode g/bhp-hr g/bhp-hr g/bhp-hr g/bhp-hr g/bhp-hr B1 Cold Hot Hot Hot Total B1+DOC Cold Hot Hot Hot Hot Hot Total S1 Cold Hot Hot Hot Total

14 Reduction (%) of the gaseous regulated pollutants by deploying DOC and lower sulfur fuel % Start mode HC CO CO 2 NOx PM DOC Cold Hot Lower sulfur fuel Cold Hot Because sulfates form a small fraction of the PM emissions, The Reductions decrease of diesel in particle PM emissions mass was through attributed the use of to the lowering fuel sulfur levels has only a limited potential as a decrease DOCs have of been soluble reported organic to be fraction in the range (Vaaraslahti of 2-65% et al., (Shah 26). et al., 27) means of PM control. However, it may have a significant effect on the particle number emissions (Ristovski et al., 26).

15 Cold start vs. Hot start PM 2.5 emitted from heavy diesel engine Start mode Concentration (mg/nm 3 ) Emission factor (g/bhp-h) Emission factor (g/l) B1 B1+DOC S1 Cold Hot Cold Hot Cold Hot In some cases catalysts can increase the.675 g/bhp-h obtained by deploying PM2.5 PM emissions, mainly by increasing the cyclone (Okuda et al., 29) sulfate content of total PM.

16 PAH emission factors of the PM2.5 for cold and hot start 1 The PAH emissions from cold start were times Total PAHs ( gg/bhp-hr) higher than those 2 from hot start. 16 B1 Cold B1 Hot B1+DOC Cold B1+DOC Hot S1 Cold S1 Hot

17 Emission factors of the toxic pollutants the pollutants in PM 2.5 sampled from primary dilution tunnel.3 the pollutants in particulate and gaseous phases sampled from secondary dilution tunnel 1.5 Total-BaPeq ( gg/bhp-hr) Total-BaPeq ( gg/bhp-hr) 1..5 particulate phase gaseous phase.5. B1 B1+DOC S1. B1 B1+DOC S1 17

18 B1 B1+DOC S1 B1 B1+DOC S B1 DPF S1 Total PCB (pg TEQ/bhp-hr) PCDD/Fs I-TEQ (pg I-TEQ/bhp-hr) Total PCB (pg TEQ/bhp-hr) PM particulate and gaseous phases B1 B1+DOC S1 PCDD/Fs I-TEQ (pg I-TEQ/bhp-hr)

19 12 PM particulate and gaseous phases 3 Total PBDE (ng/bhp-hr) 1 4 Total PBDE (ng/bhp-hr) B1 B1+DOC S1 B1 B1+DOC S1 Emission factors of the pollutants in PM 2.5 were even higher than that in total PM, except for PAHs, revealing that the artifact of MOUDI may seriously affect the results due to the adsorption of the semivolatile 19 pollutants onto the filters.

20 The toxic pollutants emitted from heavy diesel engine were all dominant as gaseous phase. The gaseous phase pollutants contributed 85.8~98.4% of total PAHs, 53.4~61.4% of total PCDD/Fs, 61.1~81.9% of total PCBs and 5.~83.7% of total PBDEs among the three tests.

21 B1 6 Particulate phase BaP eq =.232 gg/nm 3 6 Gaseous phase BaP eq =.438 gg/nm Nap AcPy Acp Flu PA Ant FL Pyr BaA CHR W e n g e r e t a l., 2 8 B a P e q =. 3 7 g g /N m 3.37 Nap PA Flu Pyr BaA CHR BbF BkF Bap IND BghiP 4 2 Nap AcPy Acp Flu PA Ant FL Pyr BaA CHR Pyrene was the major particulate-associated PAH (Wenger et al., 28; Liu et al., 28). heavy-duty diesel engine, commercial diesel fuel (Wenger et al., 28)

22 OCDD 2,3,7,8-TeCDF 1,2,3,7,8-PeCDF 2,3,4,7,8-PeCDF 1,2,3,4,7,8-HxCDF 1,2,3,6,7,8-HxCDF 2,3,4,6,7,8-HxCDF 1,2,3,7,8,9-HxCDF 1,2,3,4,6,7,8-HpCDF 1,2,3,4,7,8,9-HpCDF OCDF 2,3,7,8-TeCDD 1,2,3,7,8-PeCDD 1,2,3,4,7,8-HxCDD 1,2,3,6,7,8-HxCDD 1,2,3,7,8,9-HxCDD 1,2,3,4,6,7,8-HpCDD OCDD 2,3,7,8-TeCDF 1,2,3,7,8-PeCDF 2,3,4,7,8-PeCDF 1,2,3,4,7,8-HxCDF 1,2,3,6,7,8-HxCDF 2,3,4,6,7,8-HxCDF 1,2,3,7,8,9-HxCDF 1,2,3,4,6,7,8-HpCDF 1,2,3,4,7,8,9-HpCDF OCDF OCDD 2,3,7,8-TeCDF 1,2,3,7,8-PeCDF 2,3,4,7,8-PeCDF 1,2,3,4,7,8-HxCDF 1,2,3,6,7,8-HxCDF 2,3,4,6,7,8-HxCDF 1,2,3,7,8,9-HxCDF 1,2,3,4,6,7,8-HpCDF 1,2,3,4,7,8,9-HpCDF OCDF 1,2,3,7,8,9-HxCDD 1,2,3,4,6,7,8-HpCDD ,3,7,8-TeCDD 1,2,3,7,8-PeCDD 1,2,3,4,7,8-HxCDD 1,2,3,6,7,8-HxCDD W e n g e r e t a l., 2 8 I-T E Q = 2.5 p g I-T E Q /N m 3 1,2,3,7,8,9-HxCDD 1,2,3,4,6,7,8-HpCDD ,3,7,8-TeCDD 1,2,3,7,8-PeCDD 1,2,3,4,7,8-HxCDD 1,2,3,6,7,8-HxCDD 5 Particulate phase Gaseous phase I-TEQ=4.18 pg I-TEQ/Nm 3 4 I-TEQ=3.54 pg I-TEQ/Nm B heavy-duty diesel engine, commercial diesel fuel (Wenger et al., 28)

23 heavy duty diesel vehicles Test modes on-road sampling (highway) on-road sampling (highway) HDDV/engine type Emission Factors (pg I- TEQ/L) Ford/Cummins 385 Freightliner/Caterpillar 35 on-road sampling (city) Freightliner/Caterpillar 12 Ref. Gullett et al., 22 Cummins (B1) 121 heavy diesel engine FTP-32 Cummins (B1+DOC) 34.4 This study Cummins (S1) 66.5

24 B1 8 8 Particulate phase Gaseous phase TEQ=.185 WHO-TEQ/Nm 3 TEQ=.677 WHO-TEQ/Nm PCB-77 PCB-81 PCB-15 PCB-114 PCB-118 PCB-123 PCB-126 PCB-156 PCB-157 PCB-167 PCB-169 PCB-189 PCB-77 PCB-81 PCB-15 PCB-114 PCB-118 PCB-123 PCB-126 PCB-156 PCB-157 PCB-167 PCB-169 PCB The coplanar PCBs only contributed 4.2% of total particulate phase TEQ and 16% of total gaseous phase TEQ, respectively. 4 2

25 Exhaust B BDE-7 BDE-15 BDE-17 BDE-28 BDE-49 BDE-71 BDE-47 BDE-66 BDE-77 BDE-1 BDE-119 BDE-99 BDE-85 BDE-126 BDE-154 BDE-153 BDE-139 BDE-14 BDE-138 BDE-156 BDE-184 BDE-183 BDE-191 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE-29 2 Particulate phase 6 Gaseous phase 21.2 ng/nm ng/nm BDE-7 BDE-15 BDE-17 BDE-28 BDE-49 BDE-71 BDE-47 BDE-66 BDE-77 BDE-1 BDE-119 BDE-99 BDE-85 BDE-126 BDE-154 BDE-153 BDE-139 BDE-14 BDE-138 BDE-156 BDE-184 BDE-183 BDE-191 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE

26 The occurrences of the PBDEs in the exhausts of the vehicles further confirm the PBDE formations during the combustion processes. Bromine contents in the fuels (Marklund et al., 199; Pecherer et al., 195) could be one of the bromine sources for the PBDE formations.

27 The high density of indoor environments contaminated with PBDEs results in significant emissions when these environments exchange air with outdoors. Environ. Sci. Technol. 4, 26, Birmingham city center (site 7) 27

28 BDE-7 BDE-15 BDE-17 BDE-28 BDE-49 BDE-71 BDE-47 BDE-66 BDE-77 BDE-1 BDE-119 BDE-99 BDE-85 BDE-126 BDE-154 BDE-153 BDE-139 BDE-14 BDE-138 BDE-156 BDE-184 BDE-183 BDE-191 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE BDE-7 BDE-15 BDE-17 BDE-28 BDE-49 BDE-71 BDE-47 BDE-66 BDE-77 BDE-1 BDE-119 BDE-99 BDE-85 BDE-126 BDE-154 BDE-153 BDE-139 BDE-14 BDE-138 BDE-156 BDE-184 BDE-183 BDE-191 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE Particulate phase 21.2 ng/nm 3 Gaseous phase 91.6 ng/nm 3 BDE-7 BDE-15 BDE-17 BDE-28 BDE-49 BDE-71 BDE-47 BDE-66 BDE-77 BDE-1 BDE-119 BDE-99 BDE-85 BDE-126 BDE-154 BDE-153 BDE-139 BDE-14 BDE-138 BDE-156 BDE-184 BDE-183 BDE-191 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE Urban Areas n=14 Vehicular Exhaust Ambient air B

29 PBDE sources to the atmosphere Concentration ng/m 3 Ref. Exhaust Heavy diesel engine this study Indoor air or workplace air Bedroom (n = 2), Main living area (n = 2) Computer laboratory with the computers turned on (The room was sealed and the ventilation turned off) (n = 6) Dismantling hall of an electronics recycling facility (n = 4) that lacked any emission control or dust suppression measures (to represent the worst case scenario) GM:.46 GM:.453 Electronics facility 77 Residences (n = 34) Workplace: Office (n = 6) Other microenvironment (n = 1) Domestic (n = 14) Automobile cabins (n = 41) Allen et al., 27 Mean: 1.8 Cahill et al., 27 Mean: 65 Cahill et al., 27 Range: Median:.378 GM: ( 1 PBDEs, BDE-29).887, , ,.339 Range: Median:.21 Pettersson- Julander et al., 24 Fromme et al., 29 Chen et al., 28 Mandalakis et al., 28

30 Pollutants Reduction (%) of the toxic pollutants by deploying DOC and lower sulfur fuel Particulate phase DOC Gaseous phase Total Particulate phase lower sulfur fuel Gaseous phase Total PM PAHs PCDD/Fs PCBs PBDEs Westerholm The The reductions reductions et al. (35.6%-64.9%) (46.6%-94.4%) (21) reported of of the that the toxic emissions toxic pollutants pollutants from in a in particulate vehicle fueled phase gaseous were with phase a comparable reference showed fuel, to that that compared dehalogenation of PM. The with decrease the and low cyclic sulfur of the crack fuel, toxic had 8-1 pollutant occurred times contents more among mutagenic in the PM compounds. contribute activity some in the of particulate the pollutant phase reductions and 2-3 in times particulate higher mutagenic phases. activity in the gaseous phase emissions.

31 Conclusion PAHs, PCDD/Fs, PCBs and PBDEs could be simultaneously measured from one exhaust sample. The artifact of MOUDI may seriously affect the results due to the adsorption of the semivolatile pollutants onto the filters. The toxic pollutants emitted from heavy diesel engine were all dominant as gaseous phase. Mobile emission sources could be one of PBDE emission sources to the atmosphere. Using DOC and lowering sulfur content in fuel could reduce the toxic pollutants emitted from heavy diesel engine.

32 Thank you!!

33 BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE DE-71 (2) BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE Bromkal 7-5DE (2) BDE-17 BDE-28 BDE-49 BDE-47 BDE-66 BDE-1 BDE-99 BDE-85 BDE-154 BDE-153 BDE-138 BDE-166 BDE-183 BDE-19 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE DE-71 (1) BDE-17 BDE-28 BDE-91 BDE-51 BDE-49 BDE-48 BDE-47 BDE-74 BDE-66 BDE-42 BDE-12 BDE-1 BDE-99 BDE-119 BDE-118 BDE-85 BDE-155 BDE-154 BDE-97 BDE-11 BDE-153 BDE-139 BDE-14 BDE-138 BDE-183 BDE-191 BDE-173 BDE-181 BDE-19 BDE-197 BDE-23 BDE-196 BDE-24 BDE-25 BDE-28 BDE-27 BDE-26 BDE DE-71 (2) BDE-17 BDE-28 BDE-91 BDE-51 BDE-49 BDE-48 BDE-47 BDE-74 BDE-66 BDE-42 BDE-12 BDE-1 BDE-99 BDE-119 BDE-118 BDE-85 BDE-155 BDE-154 BDE-97 BDE-11 BDE-153 BDE-139 BDE-14 BDE-138 BDE-183 BDE-191 BDE-173 BDE-181 BDE-19 BDE-197 BDE-23 BDE-196 BDE-24 BDE-25 BDE-28 BDE-27 BDE-26 BDE Bromkal 7-5DE (2) (A) Congener profiles in the commercial PBDE mixtures 33 penta-bde mixtures BDE-47, -99, -1, -154,

34 Bromkal 79-8DE (1) BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE-29 BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE DE-79 (1) DE-79 (2) BDE-17 BDE-28 BDE-49 BDE-47 BDE-66 BDE-1 BDE-99 BDE-85 BDE-154 BDE-153 BDE-138 BDE-166 BDE-183 BDE-19 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE-29 (B) octa-bde mixtures BDE-153, -183, -197, - 196, -27, or BDE-183, -197, -23, - 27, -26,

35 BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE Bromkal 82-DE (2) BDE-17 BDE-28/33 BDE-75 BDE-51 BDE-49 BDE-48/71 BDE-47/74 BDE-66/42 BDE-12 BDE-1 BDE-99 BDE-97/118 BDE-85 BDE-126/155 BDE-154 BDE-144 BDE-153 BDE-139 BDE-14 BDE-138 BDE-184 BDE-175/183 BDE-191 BDE-18 BDE-171 BDE-21 BDE-197 BDE-23 BDE-196 BDE-194 BDE-28 BDE-27 BDE-26 BDE Saytex 12E (2) BDE-17 BDE-28 BDE-49 BDE-47 BDE-66 BDE-1 BDE-99 BDE-85 BDE-154 BDE-153 BDE-138 BDE-166 BDE-183 BDE-19 BDE-197 BDE-23 BDE-196 BDE-28 BDE-27 BDE-26 BDE DE-83 (1) BDE-17 BDE-28 BDE-91 BDE-51 BDE-49 BDE-48 BDE-47 BDE-74 BDE-66 BDE-42 BDE-12 BDE-1 BDE-99 BDE-119 BDE-118 BDE-85 BDE-155 BDE-154 BDE-97 BDE-11 BDE-153 BDE-139 BDE-14 BDE-138 BDE-183 BDE-191 BDE-173 BDE-181 BDE-19 BDE-197 BDE-23 BDE-196 BDE-24 BDE-25 BDE-28 BDE-27 BDE-26 BDE non-specific formulation (2) (C) 35 deca-bde mixtures 29