Dept. of Environmental Science
Oregon Graduate Center
This research has determined the mass and composition distribution as a function of particle size for wood burning stove and fireplace aerosols. Sampling was done from cooled, diluted smoke plumes to better describe particulate properties as they exist in the atmosphere. The particulate composition variability noted in previous research was controlled by restricting sampling to hot burning (damper open combustion) and cool burning (air starved damper closed combustion). Size distributed traffic and residential oil burner aerosols were also sampled. Samples were collected behind a series of single stage impactors. Special emphasis was placed on the determination of organic and elemental carbon because these species are major components of combustion aerosols. Corrections were made for organic vapor adsorption on quartz fiber sampling filters. Hot burning RWC particles were black, had a unimodal size distribution and contained from 20 to 60% carbon (primarily elemental carbon) and high levels of trace elements (K, S, Cl). In contrast, cool burning RWC particles were tan, had a bimodal size distribution, and contained from 55 to 65% carbon (almost entirely organic carbon) and only minute amounts of trace elements. RWC composition data were used in CMB modeling of residential area aerosol samples by: (1) using a composite RWC composition profile adjusted for the proportion of damper-open and closed burning as determined by surveys; or (2) using both hot and cool RWC profiles together. CMB modeling was used across the fine aerosol (<2.5 Î¼m) size range to show the size distribution of combustion generated aerosols. It was demonstrated that combustion generated organic and elemental carbon distributions, especially for particles <0.3 Î¼m shifted to larger sizes during their atmospheric residence time. This shift can be explained by coagulation. CMB modeling was also used to examine the effects of assuming that RWC particles lose organic carbon during their atmospheric residence time. For winter samples the agreement between organic and elemental carbon values calculated by the model and ambient values was improved by allowing RWC particles to lose from 25 to 65% of their organic carbon loading; however, allowing these losses did not significantly alter source contributions.
Rau, John Anthony, "Residential wood combustion aerosol characterization as a function of size and source apportionment using chemical mass balance modeling" (1986). Scholar Archive. 204.