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Show The Experimentai Study on Emission of Nitrogen Oxides in A 70,000 Btu/Hr Gas-fired Furnace H. K. Ma and D. M. Hsieh Department of Mechanical Engineering National Taiwan University Taiwan, R.O.C. ABSTRACT The experimental study is to investigate the control of thermal nitrogen oxides emissions from a 70,000 Btu/hr gas-fired test furnace. Tests, included changing axial or radial air flow rate, adding cooling water, and adding staged air were performed to characterize and optimize the fuel-rich burning zone and the fuel-lean burnout zone independently. Detailed measurements of 02,C0 2,CO,NO and NOx were made at the fuel-rich burning zone and furnace exit. The influence of forming CO,NO and NOx was examined. Results indicated that adding staged air in the fuelrich burning zone (75cm from burner) will reduce the maximum NO and NOx emissions. Adding cooling water in a right position may further lower the NO and NOx emissions. In addition, the least formation of thermal nitrogen oxides in the first stage fuel-rich burning zone will occur at the stoichiometric ratio's inverse value,(¢ 1)-1, 0.65 to 0.7. |