Speciation of Gas-Phase and Fine Particle Emissions from Burning of Foliar Fuels

Abstract

Fine particle matter with aerodynamic diameter <2.5 microm (PM2.5) and gas-phase emissions from open burning of six fine (foliar) fuels common to fire-prone U.S. ecosystems are investigated. PM2.5 distribution is unimodal within the 10-450 nm range, indicative of an accumulation mode. Smoldering relative to flaming combustion shows smaller particle number density per unit time and median size. Over 100 individual organic compounds in the primarily carbonaceous (>70% by mass) PM2.5 are chemically speciated by gas chromatography/mass spectrometry. Expressed as a percent of PM2.5 mass, emission ranges by organic compound class are as follows: n-alkane (0.1-2%), polycyclic aromatic hydrocarbon (PAH) (0.02-0.2%), n-alkanoic acid (1-3%), n-alkanedioic acid (0.06-0.3%), n-alkenoic acid (0.3-3%), resin acid (0.5-6%), triterpenoid (0.2-0.5%), methoxyphenol (0.5-3%), and phytosterol (0.2-0.6%). A molecular tracer of biomass combustion, the sugar levoglucosan is abundant and constitutes a remarkably narrow PM2.5 mass range (2.8-3.6%). Organic chemical signatures in PM2.5 from open combustion of fine fuels differ with those of residential wood combustion and other related sources, making them functional for source-receptor modeling of PM. Inorganic matter [PM2.5 - (organic compounds + elemental carbon)] on average is estimated to make up 8% of the PM2.5. Wavelength dispersive X-ray fluorescence spectroscopy and ion chromatography identify 3% of PM2.5 as elements and water-soluble ions, respectively. Compared with residential wood burning, the PM2.5 of fine fuel combustion is nitrate enriched but shows lower potassium levels. Gas-phase C2-C13 hydrocarbon and C2-C9 carbonyl emissions are speciated by respective EPA Methods T0-15 and T0-11A. They comprise mainly low molecular weight C2-C3 compounds and hazardous air pollutants (48 wt % of total quantified volatile organic carbon).

A spatiotemporal land-use regression model of winter fine particulate levels in residential neighbourhoods

“…We measured PM1 as wood smoke particles are generally o1 mm. 5,6 Table 1 describes the areas surveyed. The routes travelled included both high and low wood burning emission intensity areas (see below for information on how wood burning emission intensity was estimated) in order to maximise spatial variability in fine particulate levels.…”

“…Wood smoke particles are generally o1 mm, with a peak in the size distribution between 0.15 and 0.40 mm; 5,6 they can reach the deepest parts of the respiratory tract. Exposure to wood smoke particles has been associated with acute respiratory effects, including increases in respiratory symptoms, decrease in respiratory functions, emergency room visits and hospitalisations.…”

On-road vehicle emissions of glyoxal and methylglyoxal from tunnel tests in urban Guangzhou, China

“…Glyoxal and methylglyoxal can both formed from the oxidation of VOCs (Calvert et al, 2000(Calvert et al, , 2002Volkamer et al, 2001) and emitted directly from tailpipes and biomass burning Kean et al, 2001;Hays et al, 2002;Ban-Weiss et al, 2008), yet direct emissions were viewed as being minor when compared to the secondary formation (Volkamer et al, 2005;Fu et al, 2008). As for speciated carbonyls emitted by gasoline and diesel vehicles, data were mostly obtained from tunnel studies carried out in the United States more than a decade ago Kean et al, 2001;Hays et al, 2002), and the trends in carbonyl emissions from vehicles were thereafter reviewed by Ban-Weiss et al (2008). There might exist great uncertainties in estimating global emission of dicarbonyls from vehicles solely based on a few studies in the US, as carbonyl emissions from motor vehicles can be affected by the changing yet varying vehicle types, fuel compositions and emission control technologies worldwide.…”

A study of water-soluble inorganic ions in size-segregated aerosols in atmospheric pollution episode

“…This size distribution suggests that most of the potassium found in the fine and ultrafine mode is due to emissions from biomass burning and from the open burning of waste materials (Morales and Leiva 2006). In the city of Santiago, the burning of biomass from rural zones represents a second source of PM 10 and could be an important source of fine particles (Hays et al 2002). Ionic balance and ratios of cationic and anionic species and relationship between NH 4 ?…”