- Author
- Ohlemiller, T. J. | Kashiwagi, T. | Werner, K.
- Title
- Products of Wood Gasification.
- Coporate
- National Bureau of Standards, Gaithersburg, MD
- Sponsor
- Department of Energy, Washington, DC
- Report
- NBSIR 85-3127, April 1985, 114 p.
- Distribution
- AVAILABLE FROM National Technical Information Service (NTIS), Technology Administration, U.S. Department of Commerce, Springfield, VA 22161. Telephone: 1-800-553-6847 or 703-605-6000; Fax: 703-605-6900; Rush Service (Telephone Orders Only) 800-553-6847; Website: http://www.ntis.gov
- Keywords
- air pollution | gasification | stoves | smoldering combustion | thermal degradation | wood | exposure time | oxygen concentration
- Abstract
- The increasing problem of pollution from wood-burning stoves has prompted this examination of the basic gasification process of wood under conditions encompassing those in stoves. The emphasis is on the products generated when wood is heated, without flaming, in atmospheres of varying oxygen concentration (0 to 21% 02 in N2). Small wood samples (typically 4 x 4 cm face, 2-4 cm thick; white pine, red oak, plus two tests with yellow pine) were subjected to uniform radiative heat fluxes (2 to 7.8 W/cm2) on one face. Other variables were sample grain orientation, thickness, exposure time and moisture content. Sample weight was followed in some tests; sample temperature (5 thermocouples) was followed in others. In all tests, all evolved products were either monitored (H20, CO, CO2, total hydrocarbons not condensible at -40 deg. C) or trapped and analyzed (condesible organic species) by gas chromatogaphy and mass spectroscopy. Many of the trends of the major products (CO, CO2, H20, THC, total organic condensible or tar) are qualitatively intelligible in terms of the expected impact of varying temperature or oxygen level, for example. The extent of change in these major products is rather limited (factor of two to four) over the range of variables explored here. The organic condensate was difficult to analyze; it is estimated that only 20% of it was chromatogaphable. More than forty species in this chromatographable portion were positively or tentatively identified and quantified. Chromatographic fingerprints of the organic condensate indicated that its composition does not vary a great deal for the conditions examined here. The fingerprints from the radiative heating tests bear a strong resemblance to those of the smoke condensate from a wood stove.