(374al) Temperature Visualization of Alternative Fuel Particle Combustion in a Drop Tube Furnace

A method will be demonstrated for obtaining high resolution images and temperature distribution measurements for solid fuel particles during combustion. Results will be presented for particles of pulverized coal, wood, and switch grass undergoing combustion in various combustion gas conditions. High speed and high magnification images of individual particles were obtained with a high resolution color camera. Image processing and analysis are described that use the three color components of the images to determine the spatial distribution of temperature for the particle surfaces. Images were obtained in a laboratory-scale drop tube furnace that has transparent quartz retorts (drop tubes) and quartz windows to allow visualization along an 80 cm drop distance. The furnace system allows a high degree of control of temperature, pressure, and gas composition in the combustion zone. The particle size for this study is 100 micrometers, the gas temperature is 900°C, and the gas composition range is 1 to 21% oxygen. The fuels, particle sizes, and operating conditions of the furnace were selected to evaluate effectiveness of alternative fuels in comparison to coal for application in cement production and energy generation.