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Show Summary Initial results from the Phase I work have been reported as work in progress. The utility of developing several interrelated models to assess the impacts of combined oxygen enrichment and gas reburn on steel furnace N O emissions, thermal and production efficiencies has been demonstrated. C F D modelling is useful in determining the temperature and velocity profiles. This data can then be used to determine impacts on refractories and steel surface, and in placing the gas reburn fuel and O F A injectors. The C F D model also provides boundary conditions for other predictive models. The tuned zoned system model has utility in its ability to quickly parametrically investigate design and operating variations from the C F D model results with simple input changes. For the stand alone gas reburn system the importance of optimizing the recovery of heat released late in the heating zone was demonstrated. The significant economic benefit of increased production was demonstrated along with the relatively minor impact of adding gas reburn to achieve off-set N O control. References Energy and Environmental Research Corporation, Topical Report: Glass Tank NOx Emission Control With Gas Reburn Phase II - Critical Experiments, GRI-96/0139, Gas Research Institute, Chicago, Illinois, September 1996. FLUENT User's Guide, (1996) Volume 2, Release 4.4, Fluent Inc., Lebanon, NH. Leonard, B.P. (1979) "A stable and accurate convective modeling procedure based on quadratic upstream interpolation," Comput Methods Appl. Mech. Eng., Volume 19, pp. 59-98. Patankar, S.V. (1980) Numerical Heat Transfer and Fluid Flow, Hemisphere Publication Corp., Washington, D C. Pearson, S. J., Moyeda, D. K., and Koppang, R. R., Industrial Application of Gas Reburning: Topical Report, Contract Number 5091-236-2286, Gas Research Institute, Chicago, Illinois, April 1994. Smith, T. F., Shen, Z. F., and Friedman, J. N., "Evaluation of Coefficients for the Weighted Sum of Gray Gases Model," Transactions of the ASME, Vol. 104, pp. 602-608, American Society of Mechanical Engineers, November 1982. U. S. EPA, Alternative Control Techniques Document - NOx Emissions From Iron and Steel Mills, EPA-453/R-94-065, Emissions Standards Division, Office of Air Quality Planning and Standards, Office of Air and Radiation, U. S. Environmental Protection Agency, Research Triangle Park, North Carolina, September 1994. 12 |