Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Study on NO Emission with Flue Gas Dilution in Air and Fuel Sides

  • Cho Eun-Seong (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Chung Suk Ho (School of Mechanical and Aerospace Engineering, Seoul National University)
  • Published : 2005.06.01
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Abstract

Flue gas recirculation (FGR) is widely adopted to control NO emission in combustion systems. Recirculated flue gas decreases flame temperature and reaction rate, resulting in the decrease in thermal NO production. Recently, it has been demonstrated that the recirculated flue gas in fuel stream, that is, the fuel induced recirculation (FIR), could enhance much improved reduction in NO per unit mass of recirculated gas, as compared to conventional FGR in air. In the present study, the effect of dilution methods in air and fuel sides on NO reduction has been investigated numerically by using $N_2$ and $CO_2$ as diluent gases to simulate flue gases. Counterflow diffusion flames were studied in conjunction with the laminar flamelet model of turbulent flames. Results showed that $CO_2$ dilution was more effective in NO reduction because of large temperature drop due to the larger specific heat of $CO_2$ compared to $N_2$. Fuel dilution was more effective in reducing NO emission than air dilution when the same recirculation ratio of dilution gas was used by the increase in the nozzle exit velocity, thereby the stretch rate, with dilution gas added to fuel side.

Keywords

References

  1. Ahn, K. Y., Kim, H. S., Son, M. K., Kim, H. K. and Kim, Y. M., 2002, 'An Experimental Study on the Combustion Characteristics of a Low $NO_X$ Burner Using Reburning Technology,' KSME Int'l J., Vol. 16, No. 7, pp.950-958
  2. Arai, M., 2000, 'Flue Gas Recirculation for Low $NO_X$ Combustion System,' IJPGC2000-15073, pp. 1-10
  3. Beer, J. M., 1996, 'Low $NO_X$ Burners for Boilers, Furnaces, and Gas Turbines ; Drive Towards the Low Bonds of $NO_X$ Emissions,' Combust Sci. and Tech., Vol. 121, pp. 169-191 https://doi.org/10.1080/00102209608935593
  4. Cho, E. -S., Sung, Y., and Chung, S. H., 2003, 'An Experiment on Low $NO_X$ Combustion Characteristics in a Multi-Staged Burner,' Trans. of KSME (B), Vol. 27, No. 1, pp. 32-38 https://doi.org/10.3795/KSME-B.2003.27.1.032
  5. Cho, E. -S. and Chung, S. H., 2004, 'Characteristics of $NO_X$ Emission with Flue Gas Dilution in Air and Fuel Sides,' KSME Int'l J., Vol. 18, No. 12, pp.2302-2308
  6. Choi, K. -M. and Katsuki, M., 2002, 'Chemical Kinetic Study on the Reduction of Nitric Oxide in Highly Preheated Air Combustion,' Proc. of Comb. Institute, Vol. 29, pp. 1165-1171 https://doi.org/10.1016/S1540-7489(02)80147-X
  7. Feese, J. J. and Turns, S. R., 1998, 'Nitric Oxide Emissions from Laminar Diffusion Flames:Effects of Air-Side versus Fuel-Side Diluent Addition,' Comb. and Flame, Vol. 113, pp.66-78 https://doi.org/10.1016/S0010-2180(97)00217-4
  8. Lang, J., 1994, 'Low $NO_X$ Burner Design Achieves Near SCR Levels,' ASME, PWR-Vol. 24, pp. 127-131
  9. Nishioka, M., Nakagawa, S., Ishikawa, Y., and Takeno, T., 1994, 'NO Emission Characteristics of Methane-Air Double Flame,' Combust. Flame, Vol. 98, pp. 127-138 https://doi.org/10.1016/0010-2180(94)90203-8
  10. Wlinning, J. A. and WUnning, J. G., 1997, 'Flameless Oxidation to Reduce Thermal NO-Formation,' Prog. Energy Combust. Sci., Vol. 23, pp. 81-94 https://doi.org/10.1016/S0360-1285(97)00006-3
  11. Giovangigli, V. and Smooke, M. D., 1987, 'Calculation of Extinction Limits for Premixed Laminar Flames in a Stagnation Flames in a Stagnation Points Flow,' J. Comp. Phys., Vol. 68, pp. 327-345 https://doi.org/10.1016/0021-9991(87)90061-1
  12. Gordon, S. and McBride, B. J., 1971, 'Computer Program for Calculation of Complex Chemical Equilibrium Compositions, Rocket Performance, Incident and Reflected Shock, and Chapman-Jouguet Detonations,' NASA SP-273, Washington D.C.
  13. Lee, S. D. and Chung, S. H., 1994, 'On the Structure and Extinction of Interacting Lean Methane/Air Premixed Flames,' Combust. Flame, Vol. 98, pp. 80-92 https://doi.org/10.1016/0010-2180(94)90199-6
  14. Kee, R. J., Ruply, F. M., and Miller, J. A., 1996, 'CHEMKIN-III : A Fortran Chemical Kinetics Package for the Analysis of Gas-Phase Chemical and Plasma Kinetics,' SAND 96-8216, Sandia National Laboratories Report
  15. Kee, R. J., Dixon-Lewis, G., Warnatz, J., Coltrin, M. E., and Miller, J. A., 1986, 'A Fortran Computer Code Package for the Evaluation of Gas-Phase Multicomponent Transport Properties,' SAND 86-8246, Sandia National Laboratories Report
  16. Smith, G. P., Golden, D. M., Frenklach, M., Moriarty, N. W., Eiteneer, B., Goldenberg, M., Bowman, C. T., Hanson, R. K., Song, S., Gardiner Jr., W. C., Lissianski, V. V., and Qin, Z., 2000, 'Gri-Mech 3.0,' http://www.me.berkeley.edu/ gri_mech/
  17. Sohn, C. H., Jeong, I. M., and Chung, S. H., 2002, 'Numerical Study of the Effects of Pressure and Air-Dilution on NO Formation in Laminar Counterflow Diffusion Flames of Methane in High Temperature Air, https://doi.org/10.1016/S0010-2180(02)00366-8
  18. Takeno, T. and Nishioka, M., 1993, 'Species Conservation and Emission Indices for Flames Described by Similarity Solutions,' Combust. Flame, Vol. 92, pp.465-468 https://doi.org/10.1016/0010-2180(93)90157-X