HR: 1340h
AN: A23C-0819    [Abstracts]
TI: Optical and Chemical Properties of Particles Generated by Traditional Wood Burning Cook Stoves
AU: * Roden, C A
EM: croden@uiuc.edu
AF: Dept. of Civil & Environmental Engineering, University of Illinois at Urbana-Champaign, Newmark Civil Engineering Lab 205 N. Mathews , Urbana, IL 61801 United States
AU: Bond, T C
EM: yark@uiuc.edu
AF: Dept. of Civil & Environmental Engineering, University of Illinois at Urbana-Champaign, Newmark Civil Engineering Lab 205 N. Mathews , Urbana, IL 61801 United States
AB: Some 2-3 billion people in the world use biofuel as their primary energy source for domestic fuel needs. It is estimated that the combustion of biofuel generates 20% of all carbonaceous aerosols. What are the characteristics of the particles emitted during biofuel use? How are these millions of small sources affecting the world around us, and are they adequately represented in today's climate models? Cooking fires have been replicated and measured in laboratory settings, but are the results representative of real-world combustion? Lack of knowledge about the characteristics and quantities of emissions from small combustion sources is a large contributor to uncertainties in global emission inventories of particulate matter. In the past, real-time field measurements at remote locations have been difficult to obtain for many reasons including limited access to sources, and the lack of power to operate measurement equipment. In order to facilitate measurements at a wide range of potential sampling sites, we designed and built a portable, battery-operated emission sampling cart. This sampling cart measures real-time data with a Particle Soot Absorption Photometer (PSAP), a Nephelometer, a CO sensor, and a CO2 sensor. Additionally, we captured the particles on filters for later analysis. We have developed working relationships with non-profit organizations in the United States and in developing countries, which afford us access to ongoing measurements of small sources, including traditional and improved wood burning cook stoves. With their help, we were able to obtain measurements from cook stove fires as operated. We present real-time measurements of optical properties including light absorption at three wavelengths (450, 550, and 700 nm), light scattering, and CO to CO2 ratio from cooking fires in Honduras. Fifteen sample data sets were measured over a two-week period. The data sets were collected from a variety of locations, over varying sample periods of at least two hours and from different wood fuels. We include a qualitative discussion of differences between the practices used in laboratory and real-world fires. From the real-time data, we derive emission factors for particle mass, elemental and organic carbon. From studies on open biomass burning, it is known that particle characteristics vary between "flaming" and "smoldering" combustion, with "flaming" combustion producing more elemental carbon. We discuss the differences in particle characteristics during different phases of combustion, as well as the relative quantities of particles produced during flaming and smoldering. We also include integrated samples of particle mass and chemistry (elemental and organic carbon and ions) taken concurrently with the optical measurements. We provide a comparison of predicted and measured optical properties of these particles. We examine how these measurements compare with previous results from laboratory studies. Finally, we discuss the implications of these data for the results of global climate modeling.
DE: 4801 Aerosols (0305)
DE: 1610 Atmosphere (0315, 0325)
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting