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Show ABSTRACT Effect of Fuel Gas Composition and Excess Air on VOC Emissions and Flame Structure of a Small-Scale Industrial Burner c. F. Edwards and P. J. Goix Combustion Research Facility Sandia National Laboratories Livennore, CA 94551-0969 /0-1 Furnace-out emissions of benzene, toluene, ethylbenzene, and the xylenes have been measured for a research-grade, industrial-style diffusion flame burner operating ,under well-controlled conditions representative of refmery process heaters. Flame structure was also evaluated by means of visible emission imaging. Excess air was varied from 50% to sub-stoichiometric. The fuels were methane and blends of methane, hydrogen, and propane used to simulate the process gas burned in refmeries. Each fuel was tailored so that the inlet and boundary conditions on the flame were invariant between fuels-minimizing fluid mechanic differences. The results show emission levels < 3 ppbv for toluene and < 0.5 ppbv for the other species under nonnal fIring conditions. They also show an increase in emissions with fuel hydrogen and propane contents. Under sub-stoichiometric conditions, emissions increase by orders of magnitude, with benzene replacing toluene as the dominant emission. Key Words: Furnaces, EnvironmentaJ Combustion INTRODUcrION Among the ammendments to the U.S. Clean Air Act made in 1990, were provisions outlining how Hazardous Air Pollutant (HAP) species are to be regulated in the future. These provisions included a list of those species or classes of species considered to be hazardous, a definition of what constitutes a Major Source of those species (and is therefore subject to regulation), and - 1 - |