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Show Non-Glass Applications for Oxy-Fuel Waste Incineration For destruction efficiency, waste incinerators require high temperatures with elevated excess oxygen levels and long combustor residence times. This is an ideal recipe for NOx generation. The high adiabatic flame temperatures (5120°F on natural gas, 5800°F on fuel oil) and reduced combustion products volume of oxy-fuel burners are a natural match for this application. Waste incinerators can operate at higher temperatures with longer residence times and still produce less NOx on a mass basis. Mass basis measurement (e.g., IbslMMBtu) is mentioned here since concentration measurements (e.g., ppm) reflect the decrease in diluent nitrogen and appear high compared to air-fuel. Because of the reduced combustion products volume, equipment-from combustion chambers to post treatment -- can be reduced in size. F or liquid wastes, the ability to atomize such wastes with pure oxygen has the potential for even better destruction efficiencies. This is due to the higher flame temperatures and intimate mixing of pure oxygen with the waste liquid. The ability of oxy-fuel burners to operate with high excess oxygen levels adds flexibility to the burners' application potential. Steel The largest use of oxy-fuel burners within the steel industry is in electric arc furnaces. Oxy-fuel burners can reduce electric energy consumption by more than 10% in such applications. These burners can also help eliminate cold spots that normally occur during melting between the electrodes. By focusing a high-temperature oxy-fuel flame at the cold spots, melting is faster, more efficient and more uniform. I I Other applications in the steel industry include ladle preheating and continuous reheat furnaces. Applications for Oxy-Fuel Requiring Additional Research Petrochemical A long, narrow and highly luminous flame characterizes oxy-fuel burners on fuel gas or fuel oil. Flame lengths are typically 2 to 2 X feet for each MMBtu/hr fued. These characteristics would appear to have possible applications for vertical-cylindrical shaped heaters, where a long, narrow flame is advantageous. In addition, the OXY -THERM LE can fire up to 15 MMBtu/hr on natural gas or 18 M:MBtu/hr on fuel oil in a burner less than 12 inches square. This would allow for tighter burner circles and reduced furnace diameters. The convection section of a typical refinery heater would need attention if oxy-fuel burners were to be used. This is due to the reduced convective flow of combustion products. 7 |