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Effect of Process Gas and Burner Gas Temperature on Reaction and Thermal Deformation Characteristics in a Steam Reformer

증기 개질기의 반응 및 열변형 특성에 미치는 공정가스와 버너가스 온도의 영향

  • Han, Jun Hee (Dept. of Mechanical Systems Engineering, Chung-Ang University) ;
  • Kim, Ji Yoon (Energy Safety Research Institute, Chung-Ang University) ;
  • Lee, Jung Hee (Technology Center Offshore Plant Industries, KRISO) ;
  • Lee, Seong Hyuk (Dept. of Mechanical Engineering, Chung-Ang University)
  • 한준희 (중앙대학교 기계시스템 엔지니어링학과) ;
  • 김지윤 (중앙대학교 차세대 에너지 연구소) ;
  • 이정희 (선박해양플랜트연구소 해양플랜트 산업기술센터) ;
  • 이성혁 (중앙대학교 기계공학부)
  • Received : 2016.08.08
  • Accepted : 2016.09.09
  • Published : 2016.09.30

Abstract

This study numerically investigates the characteristics of chemical reactions and thermal deformation in a steam reformer. These phenomena are significantly affected by the high-temperature burner gas and the process gas conditions. Because the high temperature of the burner gas ranges from 800 to 1000 K, the reformer tubes undergo substantial thermal deformation, eventually resulting in structural failure. Thus, it is necessary to understand the characteristics of the reaction and thermal deformation under the operating conditions to evaluate the reformer tubes for sustainable, stable operation. Extensive numerical simulations were carried out using commercial CFD code (ANSYS FLUENT/MECHANICA Ver. 13.0) while considering three-dimensional turbulent flows and combined heat transfer including conduction, convection, and radiation. Structural analysis considering conjugated heat transfer between solid tubes and fluid flows was conducted using the Fluid-Solid Interaction (FSI) method. The results show that when the injection temperature of the process gas and burner gas decreased, the hydrogen production rate decreased significantly, and thermal deformation decreased by at least 15 to 20%.

본 연구는 전산유체역학 기법을 이용하여 수소 생산 플랜트의 개질 튜브 공정가스와 버너 가스 온도에 따른 화학반응과 열변형 특성을 분석한다. 개질로 내부의 온도는 약 800 K 내지 1000 K 이상으로 고온으로 유지되기 때문에 튜브의 열변형 문제가 심각하게 발생할 수 있다. 따라서 개질로의 구조건전성을 평가하고 안정된 생산력을 가진 장비를 운영하기 위해서 반응과 열변형 특성에 대한 이해는 필수적이다. 본 연구는 상용 전산해석 코드(ANSYS Fluent/Mechanical V.13.0)를 사용하여, 대류, 전도 및 복사 열전달을 포함한 복합 열전달과 난류유동을 3차원적으로 해석하였다. 특히, 열유동 특성에 따른 연성해석(Fluid-Solid Interaction: FSI)를 수행하였으며 고온 버너가스와 공정가스 운전조건에 따른 반응 특성과 열변형 변화를 분석하였다. 수치해석 결과, 개질 공정가스와 버너 가스의 주입온도가 각각 200 K 감소하면, 수소생성량은 최대 약 4 배, 최소 약 2 배 감소한다. 또한, 공정가스와 버너 가스의 주입온도에 따라 열변형은 최대 약 20%, 최소 약 15% 감소한다.

Keywords

References

  1. H. S. Roh, D. K. Lee, K. Y. Koo, U. H. Jung, and W. L. Yoon, "Natural gas Steam Reforming for Hydrogen Production over Metal Monolite Catalyst with Efficient Heat-transfer", International Journal of Hydrogen Energy, 35, pp. 1613-1619, 2010. DOI: http://dx.doi.org/10.1016/j.ijhydene.2009.12.051
  2. A. Demirbas, Biofuels sources, "Biofuels Policy, Biofuel Economy and Global Biofuel Projections, Energy Conversion and Management. Manage, 49, pp. 2106-2116, 2008. https://doi.org/10.1016/j.enconman.2008.02.020
  3. L. Basini, K. Aasberg-Petersen, A. Guarinoni, and M. Ostberg, "Catalytic Partial Oxidation of Natural Gas at Evlevated Pressure and Low Residence Time", Catalysis Today, 64, pp. 21-30, 2001. DOI: http://dx.doi.org/10.1016/S0920-5861(00)00504-6
  4. A. Qi, S. Wang, C. Ni, and D. Wu, "Autothermal Reforming of Gasoline on Rh-based Monolithic Catalysts", International Journal of Hydrogen Energy, 32, pp. 981-991, 2007. DOI: http://dx.doi.org/10.1016/j.ijhydene.2006.06.072
  5. H. Arbag, S. Yasyerli, N. Yasyerli, and C. Dogu, "Activity and Stability Enhancement of Ni-MCM-41 Catalysts by Rh Incorporation for Hydrogen from Dry Reforming of Methane", International journal of Hydrogen Energy, 35, pp. 2296-2304, 2010. DOI: http://dx.doi.org/10.1016/j.ijhydene.2009.12.109
  6. J. A. Liu, "Kinetics, Catalysis and Mechanism of Methane Steam Reforming", WPI Chemical Engineering Department, 2006.
  7. M.H. Shariat, A. h. Faraji, A. Ashafriahy, M. M. Alipour, "In Advanced Creep Failure of H.P. Modified Reformer Tubes in an Ammonia Plant", The Journal of Corrosion Science and Engineering, 6, pp. 1-20, 2003.
  8. L. Lao et al, "CFD Modeling and Control of a Steam Methane Reforming Reactor", Chemical Engineering Science, 148, pp. 78-92, 2016. DOI: http://dx.doi.org/10.1016/j.ces.2016.03.038
  9. M. Nikodemus, "Identifying Favorable Catalyst Design Features in Methane Steam Reforming Using Computational Fluid Dynamics", WORCESTER POLYTECHNIC INSTITUTE, 2013.
  10. G. Dixon, M. Nijemeisland, "CFD as a Design Tool for Fixed-Bed Reactors", Industrial & Engineering Chemistry Research, 40, pp. 5246-5254, 2001. DOI: http://dx.doi.org/10.1021/ie001035a
  11. M. N. Pedernera, J. Pina, D. O. Borio, and V. Bucala, "Use of a Heterogeneous Two-dimensional Model to Improve the Primary Steam Reformer Performance", Chemical Engineering Journal, 94, pp. 29-40, 2003. DOI: http://dx.doi.org/10.1016/S1385-8947(03)00004-4
  12. M. Ni, "2D Heat and Mass Transfer Modeling of Methane Steam Reforming for Hydrogen Production in a Compact Reformer", Energy Conversion and Management, 65, pp. 155-163, 2013. DOI: http://dx.doi.org/10.1016/j.enconman.2012.07.017
  13. J. Lee, J. H. Han et al, "Characteristics of Heat Transfer and Chemical Reaction of Methane-Steam Reforming in a Porous Catalytic Medium", Journal of Mechanical Science and Technology, 30, pp. 473-481, 2016. DOI: http://dx.doi.org/10.1007/s12206-015-1252-1
  14. C. G. Choi, T. Y. Chung, J. H. Nam and D. H. Shin, "A Comparative Study for Steam-Methane Reforming Reaction Analysis Model.", Transactional of the Korean Society of Mechanical Engineers B, 32, pp. 497-503, 2008. DOI: http://dx.doi.org/10.3795/KSME-B.2008.32.7.497
  15. ANSYS Mechanical, "ANSYS Mechanical APDL Theory Reference; Version 13.0.", ANSYS Inc, Canonsburg, 2013.