10.1021/es703065h.s001
Barbara Zielinska
Barbara
Zielinska
David Campbell
David
Campbell
Douglas R. Lawson
Douglas R.
Lawson
Robert G. Ireson
Robert G.
Ireson
Christopher S. Weaver
Christopher S.
Weaver
Thomas W. Hesterberg
Thomas W.
Hesterberg
Timothy Larson
Timothy
Larson
Mark Davey
Mark
Davey
L.-J. Sally Liu
L.-J. Sally
Liu
Detailed Characterization and Profiles of Crankcase and Diesel Particulate Matter Exhaust Emissions Using Speciated Organics
American Chemical Society
2008
carbon emission rates
PAH
school buses
Speciated OrganicsA monitoring campaign
engine oil
PM 2.5 diesel engine emissions
lubricating oil PM emissions
36D
road draft tubes
crankcase emissions
tailpipe PM emissions
Diesel Particulate Matter Exhaust Emissions
crankcase vent emissions
tailpipe emissions
2008-08-01 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Detailed_Characterization_and_Profiles_of_Crankcase_and_Diesel_Particulate_Matter_Exhaust_Emissions_Using_Speciated_Organics/2923915
A monitoring campaign was conducted in August−September 2005 to compare different experimental approaches quantifying school bus self-pollution. As part of this monitoring campaign, a detailed characterization of PM<sub>2.5</sub> diesel engine emissions from the tailpipe and crankcase emissions from the road draft tubes was performed. To distinguish between tailpipe and crankcase vent emissions, a deuterated alkane, <i>n</i>-hexatriacontane-d<sub>74</sub> (<i>n</i>-C<sub>36</sub>D<sub>74</sub>) was added to the engine oil to serve as an intentional quantitative tracer for lubricating oil PM emissions. This paper focuses on the detailed chemical speciation of crankcase and tailpipe PM emissions from two school buses used in this study. We found that organic carbon emission rates were generally higher from the crankcase than from the tailpipe for these two school buses, while elemental carbon contributed significantly only in the tailpipe emissions. The <i>n</i>-C<sub>36</sub>D<sub>74</sub> that was added to the engine oil was emitted at higher rates from the crankcase than the tailpipe. Tracers of engine oil (hopanes and steranes) were present in much higher proportion in crankcase emissions. Particle-associated PAH emission rates were generally very low (<1 μg/km), but more PAH species were present in crankcase than in tailpipe emissions. The speciation of samples collected in the bus cabins was consistent with most of the bus self-pollution originating from crankcase emissions.