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Show AFRC 90 Paper #20 COMBUSTION SPACE MODELLING OF OXY-FUEL FIRED GLASS MELTER Wolfgang Richter- S~ k..-r - U\ Consultant Irvine, California 92714 Hisashi Kobayashi S h 0 Union Carbide Industrial Gases Inc., Linde Division Tarrytown, New York 10561 @1990 Union Carbide Industrial Gases Technology Corporation ABSTRACT A three-dimensional heat transfer code based on the zonal method was applied to evaluate the oxygen-fuel firing of a crossfired regenerative glass melter. A furnace end section which includes the bridge wall and a pair of the regenerator ports was modelled in detail for a base air case and several oxy-fuel firing cases. The firing rates of two oxy-fuel burners that matched the heat flux distribution of the base air case were determined. The effects of the height and angle of the oxy-fuel burners on the temperature and heat flux distributions were predicted to evaluate the optimum burner placement of the oxyfuel burners. The main conclusions of the simulation are that; (1) in spite of the small flame diameters, the high momentum low flame temperature oxy-fuel burners can create temperature and heat flux distributions equivalent to those of the base air case with a wide flame and (2) both lower burner elevation and angling of the oxy-fuel burners toward the glass surface tend to increase heat transfer to glass surface and reduce the peak refractory temperatures. INTRODUCTION Oxygen-fuel firing of glass melters is ga1n1ng increasing industry acceptance as a viable way to reduce NOx, particulates and other toxic emissions and to improve energy efficiency. Small specialty glass tanks have been converted to oxygen firing and have been operating commercially for several years (Ref. 1). A 110 TPD unit melter was converted to oxygen firing about a year ago (Ref. 2). Union Carbide Industrial Gases (UCIG), Inc. has recently conducted successful oxy-fuel firing programs in large tanks for glass bottles and fibers. Since the combustion and heat transfer conditions with oxy-fuel firing can be substantially different from those with the conventional air firing, retrofit~1ng of existing air fired furnaces with oxy-fuel burners requires a careful selection of the type and number of oxy-fuel burners and their proper placement on the glass tank walls. At present these burner decisions are made based on (1) experiences in other industrial furnaces, (2) experimental data 1 |