Clean Technology (청정기술)

The Korean Society of Clean Technology (한국청정기술학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Study of Methane-hydrogen Flameless Combustion with Variation of Recirculation Rate and Hydrogen Content using 1D Opposed-flow Diffusion Flame Model of Chemkin

Chemkin 기반의 1차원 대향류 확산 화염 모델을 활용한 재순환율 및 수소 함량에 따른 메탄-수소 무화염 연소 특성 해석 연구

  • Yu, Jiho (Yonsei University) ;
  • Park, Jinje (Korea Institute of Industrial Technology) ;
  • Lee, Yongwoon (Korea Institute of Industrial Technology) ;
  • Hong, Jongsup (Yonsei University) ;
  • Lee, Youngjae (Korea Institute of Industrial Technology)
  • 유지호 (연세대학교) ;
  • 박진제 (한국생산기술연구원) ;
  • 이용운 (한국생산기술연구원) ;
  • 홍종섭 (연세대학교) ;
  • 이영재 (한국생산기술연구원)
  • Received : 2022.05.31
  • Accepted : 2022.07.08
  • Published : 2022.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

The world is striving to transition to a carbon-neutral society. It is expected that using hydrogen instead of hydrocarbon fuel will contribute to this carbon neutrality. However, there is a need for combustion technology that controls the increased NOx emissions caused by hydrogen co-firing. Flameless combustion is one of the alternative technologies that resolves this problem. In this study, a numerical analysis was performed using the 1D opposed-flow diffusion flame model of Chemkin to analyze the characteristics of flameless combustion and the chemical reaction of methane-hydrogen fuel according to its hydrogen content and flue gas recirculation rate. In methane combustion, as the recirculation rate (Kv) increased, the temperature and heat release rate decreased due to an increase in inert gases. Also, increasing Kv from 2 to 3 achieved flameless combustion in which there was no endothermic region of heat release and the region of maximum heat release rate merged into one. In H2 100% at Kv 3, flameless combustion was achieved in terms of heat release, but it was difficult to determine whether flameless combustion was achieved in terms of flame structure. However, since the NOx formation of hydrogen flameless combustion was predicted to be similar to that of methane flameless combustion, complex considerations of flame structure, heat release, and NOx formation are needed to define hydrogen flameless combustion.

세계는 탄소 중립 사회로의 전환을 추진하고 있으며, 탄화수소계 연료를 수소로 대체함으로써 탄소 중립에 대한 기여를 기대할 수 있다. 하지만 수소 연소에 따른 질소산화물을 제어하기 위한 기술이 필요하며, 무화염 연소 기술이 하나의 대안이 될 수 있다. 본 연구는 수소 함량 및 배가스 재순환율에 따른 메탄-수소 연료의 연소 및 반응 특성을 분석하기 위해 Chemkin 기반의 1차원 대향류 확산화염 모델을 이용하여 해석을 수행하였다. 메탄 연소시 재순환율이 2에서 3으로 증가할 때 열방출의 흡열 구간이 없고 최대 열방출률 영역이 하나로 병합되는 무화염 연소가 달성되었다. 재순환율 3의 수소 전소 시 열방출 측면에서 무화염 연소가 달성되었으나, 화염 구조의 측면에서는 무화염 연소 달성 여부의 판단이 어렵다. 하지만 NO 생성량은 메탄 무화염 연소와 비교하여 유사한 수준으로 예측되었기에 수소 무화염 연소를 규정하기 위해서는 화염 구조, 열방출, NOx 생성에 대한 복합적인 고려가 필요하다.

Keywords

Acknowledgement

본 연구는 2022년도 산업통상자원부의 재원으로 한국에너지기술평가원(KETEP)의 지원을 받아 수행한 연구과제입니다(No. 2022202090003A).

References

  1. https://unfccc.int/documents/267683 (accessed Apr. 2022).
  2. https://cms.law/en/deu/insight/hydrogen/hydrogen-in-the-energy-market (accessed Apr. 2022).
  3. Joo, S., Yoon, J., Kim, J., Lee, M., and Yoon, Y., "NOx emissions characteristics of the partially premixed combustion of H2/CO/CH4 syngas using artificial neural networks," Appl. Therm. Eng., 80, 436-444 (2015). https://doi.org/10.1016/j.applthermaleng.2015.01.057
  4. Huang, X., Tummers, M. J., and Roekaerts, D. J. E. M., "Experimental and numerical study of MILD combustion in a lab-scale furnace." Energy Procedia, 120, 395-402 (2017). https://doi.org/10.1016/j.egypro.2017.07.231
  5. Abuelnuor, A. A. A., Wahid, M. A., Mohammed, H. A., and Saat, A., "Flameless combustion role in the mitigation of NOX emission: a review," Int. J. Energy Res., 38(7), 827-846 (2014). https://doi.org/10.1002/er.3167
  6. Li, P., Wang, F., Mi, J., Dally, B. B., Mei, Z., Zhang, J., and Parente, A., "Mechanisms of NO formation in MILD combustion of CH4/H2 fuel blends," Int. J. Hydrog. Energy, 39(33), 19187-19203 (2014). https://doi.org/10.1016/j.ijhydene.2014.09.050
  7. Ayoub, M., Rottier, C., Carpentier, S., Villermaux, C., Boukhalfa, A. M., and Honore, D., "An experimental study of mild flameless combustion of methane/hydrogen mixtures," Int. J. Hydrog. Energy, 37(8), 6912-6921 (2012). https://doi.org/10.1016/j.ijhydene.2012.01.018
  8. Li, P., Mi, J., Dally, B. B., Wang, F., Wang, L., Liu, Z., Chen, S., and Zheng, C., "Progress and recent trend in MILD combustion," Sci. China Technol. Sci., 54, 255-269 (2011).
  9. Tu, Y., Liu, H., and Yang, W., "Flame characteristics of CH4/H2 on a jet-in-hot-coflow burner diluted by N2, CO2, and H2O," Energy Fuels, 31(3) 3270-3280 (2017). https://doi.org/10.1021/acs.energyfuels.6b03246
  10. Ziani, L., Chaker, A., Chetehouna, K., Malek, A., and Mahmah, B., "Numerical simulations of non-premixed turbulent combustion of CH4-H2 mixtures using the PDF approach," Int. J. Hydrog. Energy, 38(20), 8597-8603 (2013). https://doi.org/10.1016/j.ijhydene.2012.11.104
  11. Mardani, A., and Fazlollahi Ghomshi, A., "Numerical study of oxy-fuel MILD (moderate or intense low-oxygen dilution combustion) combustion for CH4-H2 fuel," Energy, 99, 136-151 (2016). https://doi.org/10.1016/j.energy.2016.01.016
  12. Mardani, A., Tabejamaat, S., and Hassanpour, S., "Numerical study of CO and CO2 formation in CH4/H2 blended flame under MILD condition," Combust. Flame, 160(9), 1636-1649 (2013). https://doi.org/10.1016/j.combustflame.2013.04.003
  13. Afarin, Y., and Tabejamaat, S., "Effect of hydrogen on H2/CH4 flame structure of mild combustion using the LES method," Int. J. Hydrog. Energy, 38(8), 3447-3458 (2013). https://doi.org/10.1016/j.ijhydene.2012.12.065
  14. Cellek, M. S., "Flameless combustion investigation of CH4/H2 in the laboratory-scaled furnace," Int. J. Hydrog. Energy, 45(60), 35208-35222 (2020). https://doi.org/10.1016/j.ijhydene.2020.05.233
  15. Mardani, A., and Mahalegi, H. K. M., "Hydrogen enrichment of methane and syngas for MILD combustion," Int. J. Hydrog. Energy, 44(18), 9423-9437 (2019). https://doi.org/10.1016/j.ijhydene.2019.02.072
  16. Park, J., Kim, D. and Lee, Y., "Experimental study on flameless combustion and NO emission with hydrogen-containing fuels," Int. J. Energy Res., 46(3), 2512-2528 (2022). https://doi.org/10.1002/er.7324
  17. Kee, R. J., Miller, J. A., Evans, G. H., and Dixon-Lewis, G., "A computational model of the structure and extinction of strained, opposed flow, premixed methane-air flames," Symp. (Int.) on Combust., 22(1), 1479-1494 (1989).
  18. Mardani, A., and Tabejamaat, S., "Effect of hydrogen on hydrogen-methane turbulent non-premixed flame under MILD condition," Int. J. Hydrog. Energy, 35(20), 11324-11331 (2010). https://doi.org/10.1016/j.ijhydene.2010.06.064
  19. Boussetla, S., Mameri, A., and Hadef, A., "NO emission from non-premixed MILD combustion of biogas-syngas mixtures in opposed jet configuration," Int. J. Hydrog. Energy, 46(75), 37641-37655 (2021). https://doi.org/10.1016/j.ijhydene.2021.01.074
  20. Naha, S., and Aggarwal, S. K., "Fuel effects on NOx emissions in partially premixed flames," Combust. Flame, 139(1-2), 90-105 (2004). https://doi.org/10.1016/j.combustflame.2004.07.006
  21. http://combustion.berkeley.edu/gri-mech/new21/version21/text21.html (accessed Apr. 2022)
  22. Wunning, J. A., and Wunning, J. G., "Flameless oxidation to reduce thermal NO-formation," Prog. Energy Combust. Sci., 23(1), 81-94 (1997). https://doi.org/10.1016/S0360-1285(97)00006-3
  23. Vlachos, D. G., Schmidt, L. D., and Aris, R., "Ignition and extinction of flames near surfaces: Combustion of CH4 in air," AIChE Journal, 40(6) 1005-1017 (1994). https://doi.org/10.1002/aic.690400611
  24. Wang, S., Yuan, Z., and Fan, A., "Experimental investigation on non-premixed CH4/air combustion in a novel miniature Swiss-roll combustor," Chem. Eng. Process., 139, 44-50 (2019). https://doi.org/10.1016/j.cep.2019.03.019
  25. Yu, B., Lee, S., and Lee. C., "Study of NOx emission characteristics in CH4/air non-premixed flames with exhaust gas recirculation," Energy, 91, 119-127 (2015). https://doi.org/10.1016/j.energy.2015.08.023
  26. Ning, D., Liu, Y., Xiang, Y., and Fan, A., "Experimental investigation on non-premixed methane/air combustion in Y-shaped meso-scale combustors with/without fibrous porous media," Energy Conv. Manag., 138, 22-29 (2017). https://doi.org/10.1016/j.enconman.2017.01.065
  27. Triantafyllidis, A., Mastorakos, E., and Eggels, R. L. G. M., "Large eddy simulations of forced ignition of a non-premixed bluff-body methane flame with conditional moment closure," Combust. Flame, 156(12), 2328-2345 (2009). https://doi.org/10.1016/j.combustflame.2009.05.005
  28. Muller, H., Ferraro, F., and Pfitzner, M., "Implementation of a Steady Laminar Flamelet Model for non-premixed combustion in LES and RANS simulations," 8th International OpenFOAM Workshop, Jeju, Korea (2013).
  29. De Joannon, M., Sabia, P., Cozzolino, G., Sorrentino, G., and Cavaliere, A., "Pyrolitic and oxidative structures in hot oxidant diluted oxidant (HODO) MILD combustion," Combust. Sci. Technol., 184(7-8), 1207-1218 (2012). https://doi.org/10.1080/00102202.2012.664012
  30. Szego, G. G., Dally, B. B., and Nathan, G. J., "Scaling of NOx emissions from a laboratory-scale mild combustion furnace," Combust. Flame, 154(1-2), 281-295 (2008). https://doi.org/10.1016/j.combustflame.2008.02.001
  31. Kim, D., Ahn, H., Yang, W., Huh, K. Y., and Lee, Y., "Experimental analysis of CO/H2 syngas with NOx and SOx reactions in pressurized oxy-fuel combustion," Energy, 219 (2021).
  32. Ilbas, M., Crayford, A. P., Yilmaz, I., Bowen, P. J., and Syredb, N., "Laminar-burning velocities of hydrogen-air and hydrogen-methane-air mixtures: an experimental study," Int. J. Hydrog. Energy, 31(12), 1768-1779 (2006). https://doi.org/10.1016/j.ijhydene.2005.12.007
  33. Huang, Z., Zhang, Y., Zeng, K., Liu, B., Wang, Q., and Jiang, D., "Measurements of laminar burning velocities for natural gas-hydrogen-air mixtures," Combust. Flame, 146(1-2), 302-311 (2006). https://doi.org/10.1016/j.combustflame.2006.03.003