Grantee Research Project Results
2000 Progress Report: The Contribution of Biomass Combustion to Ambient Fine Particle Concentrations in the United States
EPA Grant Number: R826233Title: The Contribution of Biomass Combustion to Ambient Fine Particle Concentrations in the United States
Investigators: Cass, Glen , Fine, Philip M.
Current Investigators: Cass, Glen , Fine, Philip M. , Seinfeld, John
Institution: California Institute of Technology
EPA Project Officer: Hahn, Intaek
Project Period: February 1, 1998 through January 31, 2001
Project Period Covered by this Report: February 1, 2000 through January 31, 2001
Project Amount: $532,642
RFA: Ambient Air Quality (1997) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Air
Objective:
The objective of this project is to quantify the contribution of biomass combustion sources to atmospheric fine particle concentrations throughout the United States. Both the spatial and seasonal variation of biomass smoke concentrations will be determined.Progress Summary:
The majority of the work completed in the past year has been related to the gas chromatography/mass spectrometry (GC/MS) analysis of the wood stove source test samples and the preparation of a series of research papers on both the fireplace and wood stove source tests. In addition, an analysis was conducted to determine regional differences in residential wood combustion source profiles throughout the United States. Plans for additional source tests on agricultural burning and prescribed burning fuels currently are being finalized. Via review of available data on agricultural and prescribed burning practices in the United States, the most important agricultural and prescribed burning fuel types have been chosen. Extraction and analysis of the 1995 set of IMPROVE filters also are being conducted.Chemical analyses of the fine particle filter samples obtained from the wood stove source tests have been completed. The GC/MS analysis of the fine particle samples from the wood stove source tests revealed over 250 individual organic compounds that have been positively identified and quantified. Almost all of the compounds also were identified in the fireplace emissions, but with sometimes different emission rates. The same trends were observed between the emission from softwoods and hardwoods. The polycyclic aromatic hydrocarbon (PAH) fraction of total fine particle emissions tended to be higher from the wood stove relative to the fireplace. As was the case for the fireplace results, the cellulose pyrolysis product levoglucosan was found as a major component in all of the fine particle emissions from wood stove wood combustion and remains a good candidate as a molecular tracer for wood combustion in general. The fine particle mass emission rates from the wood stove ranged between 0.9 and 3.4 grams per kilogram of wood burned, generally less than the fireplace source tests for the same wood species. The use of the catalytic bed of the wood stove did not have appreciable effects on fine particle mass emission rates. However, PAH and elemental carbon emissions were relatively higher when the catalyst was engaged.
Regional emission factors for residential wood combustion were calculated based on wood burning activity, combustion appliance type, wood species distributions, and the emission factors derived from the source testing program. It was found that significant differences among U.S. regions exist largely due to the different availability of hardwoods and softwoods. There also are some differences in the regional emissions profiles with respect to the relative amounts of certain resin acids emitted from different areas. These results confirm the hypothesis that a single residential wood combustion source profile may not be applicable to the entire United States.
Future Activities:
In the coming months, a series of source tests will be conducted on the most important agricultural and prescribed burning fuels in the United States. Subsequently, analysis of the emissions from these tests will be completed. The extraction and analysis of the nationwide collection of ambient samples from the IMPROVE network for 1995 will continue and be completed as well. Finally, the results from the source tests and the ambient filter analysis will be combined in chemical mass balance receptor models to determine the contribution of biomass combustion to ambient fine particle levels in the United States.Journal Articles:
No journal articles submitted with this report: View all 12 publications for this projectSupplemental Keywords:
air, ambient air, particulates, organics, environmental chemistry, analytical, engineering, measurement methods, wood burning., RFA, Air, Scientific Discipline, particulate matter, Environmental Chemistry, Environmental Monitoring, incineration, chemical characteristics, smoke concentrations, organic chemical trace techniques, atmospheric chemistry, fine particles, seasonal variation, particulates, biomass combustion, ambient air quality, air toxicsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.