Atomization of Coal-Water Slurry Using a Pulse Combustor

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ATOMIZATION OF COAL WATER SLURRY USING A PULSE COMBUSTOR by David W. Shaw and George A. Richards u.S. Department of Energy Morgantown Energy Technology Center American Flame Research Committee 1989 International Symposium on Combustion in Industrial Furnaces and Boilers September 25-27, 1989 Short Hills, New Jersey ABSTRACT Preliminary experiments using a propane fired pulse combustor to atomize coal water slurry (CWS) have shown that the size distribution of the particles in the slurry can essentially be recovered by this atomization method. This technique addresses the significant practical problem of delivery and atomization of CWS fuels. Conventional airblast atomizers typically require air to liquid ratios of 0.5:1 or more, and pressure ratios of around 2:1. For proposed coal-fired gas turbines this can be a significant factor in compressor sizing, and also lowers the effective combustion air temperature when using cool atomizing air. Calculations for a simple cycle have shown that efficiency of a coal fired gas turbine system can be moderately improved by elimination of the extra boost compressor required for airblast atomization. Even with the high pressure ratios airblast atomizers produce droplets which are agglomerates of several smaller coal particles from the finely ground coal in the slurry.