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Show • The formation of N O x in the 0 2/C02 gas mixtures appears to show a strong correlation with both the increasing flame temperature and oxygen partial pressures. The N O x values for the air combustion case appears to fall within this pattern of increasing flame temperatures; in spite of higher thermal N O x formation that is not a characteristic of fuel burning in the 02/C02 gas mixtures. • In the absence of in-flame measurements, flue gas compositions also indicate an increasing S 0 2 concentration with the higher oxygen, 02/C02 gas mixtures. The lowest S02 concentration was measured for coal combustion in air. • The flue gas CO content when burning coal in the 02/C02 gas mixtures is higher than for fuel combustion in air. However, the higher C O values in the range of 30-40 ppmv are relatively insignificant and not detrimental to equipment or plant personnel. • No significant morphological changes were noted in the character of the furnace and fly ash residues except for a tendency towards increased slagging of the near burner residues for coal combustion in the 3 5 % oxygen concentration 02/C02 gas mixture. • Measured and calculated values of the carbon burnout efficiencies for the 02/C02 tests are in the + 9 9 % range and comparable to that monitored for coal combustion in air. Acknowledgments Funding by the Alberta Energy Coal R&D Program (for the design phase in FY 1994/95), the Canadian Electricity Association, Saskatchewan Power Corporation, TransAlta Utilities, Environment Canada, Canadian Liquid Air, United States Department of Energy through the IEA Greenhouse Gas R & D Programme and Natural Resources Canada through the Panel on Energy R & D (PERD) is gratefully acknowledged. Bibliography 1. Thambimuthu, K.V., Conrad C, Palmer, A., Sellers, T.J. and Nadarajah, A., 1996, 'Novel C 0 2 Reduction Technology: Fossil Fuel Combustion in an 02/C02 Medium', Proceedings Combustion Canada 1996 Conference, Radisson Hotel, June 5-7, Ottawa, Canada. 2. Miyamae, S., Kiga, T., Takano, S., Omata, S. and Kimura, N., 1994, "Bench-scale Testing on 0 2/C02 combustion for C 0 2 Recovery", Paper presented at the JFRC/AFRC Symposium on Combustion, Hawaii, USA. 19 31 13 |