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Show Application of a Comprehen ive Combu tion Code to Simulate NO Pollutant Forn1ation in a Utility-Scale Furnace Scott C. Hill* and John N. Cannon+ Advanced Combustion Engineering Research Center Brigham Young University A comprehensive combustion code, PCGC-3, is used to simulate the flow, combustion, and NO pollutant formation processes in a 85 MWe coal-fired utility boiler. The code is used to predict NO emissions from the boiler under various operating conditions. The conditions tested in this study are: over-fire air, % excess air, and burner tilt. Code predictions are compared with effluent NO measurements made in this boiler. These comparisons show good agreement between model predictions for some observed trends, and demonstrate that the computer code is a useful tool which can provide insights into boiler operation. Comparisons which do not show the conect trend suggest that a finer grid resolution is required to correctly predict some trends. Introduction The world has large reserves of coal, which make up 70% of the known world reserves of fossil fuels, and a large fraction of the world's speculative reserves.} Coal is cunently used to meet a significant portion of the world's energy needs, and that fraction is likely to increase in the coming years as the reserves of other fossil fuels are depleted. Coal typically contains 1-2% nitrogen which is chemically bound in the coal structure. This nitrogen is commonly referred to as fuel nitrogen. During combustion or gasification, the fuel nitrogen in the coal is converted to nitrogencontaining (NOx) pollutants (NO, N02, N20, HCN, NH3). The species formed depend principally * Research Associate, ACERC + Emeritus Professor of Mechanical Engineering |