Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지
DOI QR코드

DOI QR Code

Influence of Mixture Non-uniformity on Methane Explosion Characteristics in a Horizontal Duct

수평 배관의 메탄 폭발특성에 있어서 불균일성 혼합기의 영향

  • Ou-Sup Han (Occupational Safety & Health Research Institute, KOSHA) ;
  • Yi-Rac Choi (Occupational Safety & Health Research Institute, KOSHA) ;
  • HyeongHk Kim (Occupational Safety & Health Research Institute, KOSHA) ;
  • JinHo Lim (Occupational Safety & Health Research Institute, KOSHA)
  • 한우섭 (한국산업안전보건공단 산업안전보건연구원) ;
  • 최이락 (한국산업안전보건공단 산업안전보건연구원) ;
  • 김형욱 (한국산업안전보건공단 산업안전보건연구원) ;
  • 임진호 (한국산업안전보건공단 산업안전보건연구원)
  • Received : 2023.07.03
  • Accepted : 2023.10.20
  • Published : 2024.02.01
Download PDF
⟨ Previous Next ⟩

Abstract

Fuel gases such as methane and propane are used in explosion hazardous area of domestic plants and can form non-uniform mixtures with the influence of process conditions due to leakage. The fire-explosion risk assessment using literature data measured under uniform mixtures, damage prediction can be obtained the different results from actual explosion accidents by gas leaks. An explosion characteristics such as explosion pressure and flame velocity of non-uniform gas mixtures with concentration change similar to that of facility leak were examined. The experiments were conducted in a closed 0.82 m long stainless steel duct with observation recorded by color high speed camera and piezo pressure sensor. Also we proposed the quantification method of non-uniform mixtures from a regression analysis model on the change of concentration difference with time in explosion duct. For the non-uniform condition of this study, the area of flame surface enlarged with increasing the concentration non-uniform in the flame propagation of methane and was similar to the wrinkled flame structure existing in a turbulent flame. The time to peak pressure of methane decreased as the non-uniform increased and the explosion pressure increased with increasing the non-uniform. The ranges of KG (Deflagration index) of methane with the concentration non-uniform were 1.30 to 1.58 [MPa·m/s] and the increase rate of KG was 17.7% in methane with changing from uniform to non-uniform.

메탄, 프로판 등을 주성분으로 하는 연료가스는 폭발위험장소에서 사용될 수 있으며, 누출로 인한 공정조건의 영향으로 불균일한 혼합기를 형성할 수 있다. 균일한 혼합기를 대상으로 측정된 문헌 데이터를 이용한 화재 폭발 위험성 평가, 손상 예측은 가스 누출에 의한 실제 폭발 사고와 다른 결과를 얻을 수 있다. 본 연구에서는 가스 누출시 나타날 수 있는 농도 변화에 있어서 불균일성 혼합기의 폭발압력, 화염속도 등의 폭발특성을 조사하였다. 길이 0.82 m의 스테인리스 재질의 밀폐 배관에서 수행하였으며 컬러 초고속 카메라 및 압력 센서를 사용하여 관찰하였다. 또한 배관 내의 시간에 따른 농도차이 변화에 대해 회귀분석 모델을 사용하여 불균일 혼합물의 정량화 방법을 제안하였다. 본 연구의 농도 불균일성 조건에 있어서 메탄 폭발 시 전파화염은 불균일성 농도가 높아짐에 따라 화염 면적의 증가가 관찰되었고 이는 난류 화염의 주름진 화염 구조와 유사하였다. 메탄의 최대압력까지 걸리는 소요시간은 불균일성이 클수록 감소하였고, 폭발압력은 불균일성이 클수록 증가하였다. 농도가 불균일한 메탄의 KG(폭연지수)의 범위는 1.30~1.58 [MPa·m/s]으로서 메탄의 농도가 균일성에서 불균일성로 변화하면서 17.7% 증가하였다.

Keywords

Acknowledgement

본 논문은 2022년도 산업안전보건연구원의 자체연구과제 "폭발위험장소의 불균일 가스혼합기에 의한 화재폭발 위험성 연구(ISBN 979-11-92782-09- 6)"의 수행된 결과의 일부입니다.

References

  1. Database for Major Industrial Accidents, Korea Occupational Safety and Health Agency(KOSHA), (2010~2019).
  2. Metghalchi, M. and Keck, J. C., "Laminar Burning Velocity of Propane-air Mixtures at High Temperature and Pressure," Combustion and Flame, 38, 143-154(1980). https://doi.org/10.1016/0010-2180(80)90046-2
  3. Razus, D., Brinzea, V., Mitu, M. and Oancea, D., "Temperature and Pressure Influence on Explosion Pressures of Closed Vessel Propane-air Deflagrations," J. Hazard. Mater., 174, 548-555(2010). https://doi.org/10.1016/j.jhazmat.2009.09.086
  4. Cashdollar, K. L., Zlochower, I. S., Green, G. M., Thomas, R. and Hertzberg, M., "Flammability of Methane, Propane, and Hydrogen Gases," J. Loss Prev. Process Ind., 13, 327-340(2000). https://doi.org/10.1016/S0950-4230(99)00037-6
  5. Bauwens, C. R., Bergthorson, J. M. and Dorofeev, S. B., "Experimental Study of Spherical-flame Acceleration Mechanisms in Large-scale Propane-air Flames," Proceedings of the Combustion Institute, 35(2), 2059-2066(2015). https://doi.org/10.1016/j.proci.2014.06.118
  6. Planas-Cuchi, E., Vilchez, J. A. and Casal, J., "Fire and Explosion Hazards during Filling-emptying of Tanks," J. Loss Prev. Process Ind., 12, 479-483(1999). https://doi.org/10.1016/S0950-4230(99)00016-9
  7. Molnarne, M., Mizsey, P. and Schroder, V., "Flammability of Gas Mixtures Part 2: Influence of Inert Gases," J. Hazard. Mater., 121, 45-49(2005). https://doi.org/10.1016/j.jhazmat.2005.01.033
  8. Chen, C. C., Liaw, H. J., Wang, T. C. and Lin, C. Y., "Carbon Dioxide Dilution Effect on Flammability Limits for Hydrocarbons," J. Hazard. Mater., 163, 795-803(2009). https://doi.org/10.1016/j.jhazmat.2008.07.051
  9. Giurcan, V., Mitu, M., Movileanu, C., Razus, D. and Oancea, D., "Influence of Inert Additives on Small-scale Closed Vessel Explosions of Propane-air Mixtures," Fire Safety Journal, 111, 102939 (2020).
  10. Liu, Y., Zhang, Y., Zhao, D., Bai, M. and Shu C. M., "Effects of Initial Temperature and Pressure on Explosion Characteristics of Propane-diluent-air Mixtures," J. Loss Prev. Process Ind., 72, 104585(2021).
  11. Zheng, K., Wu, Q., Chen, C., Xing, Z., Hao, Y. and Yu, M., "Explosion Behavior of Non-uniform Methane-air Mixture in an Obstructed Duct with Different Blockage Ratios," Energy, 255(15), 124603 (2022).
  12. Gao, J., Ai, B., Hao, B., Guo, B., Hong, B. and Jiang, X., "Effect of Obstacles Gradient Arrangement on Non-Uniformly Distributed LPG-Air Premixed Gas Deflagration," Energies, 15, 6872 (2022).
  13. Harayama, M., Ohtano, H., Hirano, T. and Akita, K., "Explosion of Combustible Gaseous Mixtures with Non-Uniform Concentration Distrbution," Japan Society for Safety Engineering, 19(5), 266-271(1980).
  14. Bae, J. I., Kim, Y. S., Seo, Y. C. and Shin, C. S., "Explosion Characteristics of Nonhomogeneous LPG-Air Mixtures," Journal of KIIS, 8(4), 114-119(1993).
  15. Sochet, I., Lamy, T. and Brossard, J., "Experimental Investigation on the Detonability of Non-uniform Gaseous Mixtures," Shock Waves, 10, 363-376(2000). https://doi.org/10.1007/s001930000066
  16. Kim, S. S. and Jang, G. H., "Effect of Non-uniform Concentration on Gas Explosion," KIGAS, 7(4), 14-19(2003).
  17. Hjertager, B. H., Bjorkhaug, M. and Fuhre, K., "Explosion Propagation of Non-homogeneous Methane-air Clouds inside An Obstructed 50 m3  Vented Vessel," J. Hazard. Mater., 19(2), 139- 153(1988). https://doi.org/10.1016/0304-3894(88)85045-3
  18. Han, O. S., "Study on Analysis Model and Effect Factors in Fire and Explosion Accidents," Occupational Safety & Health Research Institute, KOSHA, 2016-OSHIR-1254, 6-8(2016).
  19. Dobashi, R., Kawamura, S., Kuwana, K. and Nakayama, Y., "Consequence Analysis of Blast Wave from Accidenal Gas Explosion," Proc. Combust. Inst., 33, 2295-2301(2011). https://doi.org/10.1016/j.proci.2010.07.059
  20. Gostintsev, Y. A., Fortov, V. E. and Shatskikh, Y. V., "The Selfsimilar Law of Propagation and Fractal Surface Structure of the Free Extending Turbulent Spherical Flame," Doklady Physical Chemistry, 397, 141-144(2004).
  21. Kim, W. K., Endo, T., Mogi, T., Kuana, K. and Dobashi, R., "Wrinkling of Large-scale Flame in Lean Propane-air Mixture due to Cellular Instabilities," Combust. Sci. Technol., 191, 491-503 (2019). https://doi.org/10.1080/00102202.2018.1502757
  22. Andrews, G. E. and Bradley, D., "The Burning Velocity of MethaneAir Mixtures," Combustion and Flame, 19(2), 275-288(1972). https://doi.org/10.1016/S0010-2180(72)80218-9
  23. Anupam, G., Natalia, M. M., Karl, P. C. and Deanna, A. L., "Laminar Burning Velocity of Hydrogen, Methane, Ethane, Ethylene and Propane Flames at near-crogenic Temperature," Application in Energy and Combustion Science, 12, 100094(2022).
  24. NFPA 68, Standard on Explosion Protection By Deflagration Venting, National Fire Protection Association(2018).
  25. Li, X., Zhang, H., Bai, S., Dong, C., Ye, X. and Jia, S., "Analysis of the Effect Mechanism of Water and CH4 Concentration on Gas Explosion in Confined Space," J. Saudi Chem. Soci., 25, 101363 (2021).
  26. Kundu, S., Zanganeh, J. and Moghtaderi, B., "A Review on Undestanding Explosion from Methane-air mixture," J. Loss Prev. Process Ind., 40, 507-523(2016). https://doi.org/10.1016/j.jlp.2016.02.004
  27. Kuznetsov, M., Ciccarelli, G., Dorofeev, S., Alekseev, V., Yankin, Y. and Kim, T., "DDT in Methane-air Mixtures," Shock Wave., 12, 215-220(2002). https://doi.org/10.1007/s00193-002-0155-0
  28. Zhang, Q., Pang, L. and Liang, H., "Effect of Scale on the Explosion of Methane in air and its Shockwave," J. Loss Prev. Process Ind., 24, 43-48(2011). https://doi.org/10.1016/j.jlp.2010.08.011
  29. Dobashi, R., "Experimental Study on Gas Explosion Behavior in Enclousure," J. Loss Prev. Process Ind., 10(2), 83-89(1997). https://doi.org/10.1016/S0950-4230(96)00050-2
  30. Lei, B., Xiao, J., Kuznetsov, M. and Jordan, T., "Effects of Heat Transfer Mechanism on Methane-air Mixture Explosion in 20L Spherical Device," J. Loss Prev. Process Ind., 80, 104864 (2022).