An Experimental and Numerical Study on the Oxy-MILD Combustion at Pilot Scale Heating Capacity

Title & Authors
An Experimental and Numerical Study on the Oxy-MILD Combustion at Pilot Scale Heating Capacity
Cha, Chun-Loon; Lee, Ho-Yeon; Hwang, Sang-Soon;

Abstract
MILD (Moderate and Intense Low-oxygen Dilution) combustion using oxygen as an oxidizer is considered as one of the most promising combustion technologies for high energy efficiency and for reducing nitrogen oxide and carbon dioxide emissions. In order to investigate the effects of nozzle angle and oxygen velocity conditions on the formation of oxygen-MILD combustion, numerical and experimental approaches were performed in this study. The numerical results showed that the recirculation ratio ($\small{K_V}$), which is an important parameter for performing MILD combustion, was increased in the main reaction zone when the nozzle angle was changed from 0 degrees to 15 degrees. Also, it was observed that a low and uniform temperature distribution was achieved at an oxygen velocity of 400 m/s. The perfectly invisible oxy-MILD flame was observed experimentally under the condition of a nozzle angle of $\small{10^{\circ}}$ and an oxygen velocity of 400 m/s. Moreover, the NOx emission limit was satisfied with NOx regulation of less than 80 ppm.
Keywords
MILD(Moderate and Intense Low-oxygen Dilution) combustion;Oxy-fuel combustion;Recirculation ratio;Dilution effect;Entrainment effect;
Language
Korean
Cited by
References
1.
Lee, C. S. and Jeon, J. Y., 2012, Activities on IEA/ECERC Delegation of Korea, Journal of Korean Society of Combustion, Vol. 17, No. 4, pp. 1-4.

2.
Li, J., Yang, W., Blasiak, W., and Ponzio, A., 2012, Volumetric combustion of biomass for \$CO_2\$ and NOx reduction in coal-fired boilers, Fuel, Vol. 102, pp. 624-633.

3.
Yang, B. O. and Lim, I. G., 1999, Experimental Study on High Temperature Air Regenerative Combustion System, 19th KOSCO Symposium, pp. 189-200.

4.
von Schéele, J., 2009, Use of direct flame impingement oxyfuel, Ironmaking and Steel-making, Vol. 36, No. 7, pp. 487-490.

5.
von Scheele, J., Gartz, M., Paul, R., Lantz, M. T., Riegert, J. P., and Soderlund, S., 2008, Flameless oxyfuel combustion for increased production and reduced \$CO_2\$ and NOx emission, Stahl und Eisen, Vol. 128, No. 7, pp. 35-40.

6.
Wunning, J. A. and Wunning, J. G., 1997, Flameless oxidation to reduce thermal NO-Formation, Progress in Energy and Combustion Science, Vol. 23, No. 1, pp. 81-94.

7.
Szego, G. G., Dally, B. B., and Nathan, G. J., 2009, Operational characteristics of a parallel jet MILD combustion burner system, Combustion and Flame, Vol. 156, No. 2, pp. 429-438.

8.
Parente, A., Malik, M. R., Contino, F., Cuoci, A., and Dally, B. B., 2016, Extension of the Eddy Dissipation Concept for turbulence/chemistry interactions to MILD combustion, Fuel, Vol. 163, pp. 98-111.

9.
Frenklach, M., Wang, H., Goldenberg, M., Smith, G. P., Golden, D. M., Bowman, C. T., Hanson, R. K., Gardiner, W. C., and Lissianski, V., 1995, GRI-Mech-An Optimized Detailed Chemical Reaction Mechanism for Methane Combustion, Gas Research Institute Topical Report, No. GRI-95/0058, Transfer, Vol. 106, pp. 774-781.