Effect of oxygen distribution for hot spot and carbon deposition minimization in a methane autothermal reforming reactor

  • Lee, Shin-Ku (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Bae, Joong-Myeon (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Kim, Yong-Min (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Park, Joong-Uen (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST) ;
  • Lim, Sung-Kwang (School of Mechanical, Aerospace and Systems Engineering, Division of Mechanical Engineering, KAIST)
  • Published : 2008.11.05

Abstract

In autothermal reforming reaction, oxygen to carbon ratio (OCR) and steam to carbon ratio (SCR) are significant factors, which control temperature and carbon deposition into the reactor. The OCR is more sensitive than the SCR to affect the temperature distribution and reforming efficiency. In conventional operation, hydrocarbon fuel, steam, and oxygen was homogeneously mixed and injected into the reactor in order to get hydrogen-rich gas. The temperature was abruptly raised due to fast oxidation reaction in the former part of the reactor. Deactivation of packed catalysts can be accelerated there. In the present study, therefore, the effect of the oxygen distribution is introduced and investigated to suppress the carbon deposition and to maintain the reactor in the mild operating temperature (e.g., $700{\sim}800^{\circ}C$). In order to investigate the effect numerically, the following models are adopted; heterogeneous reaction model and two-medium model for heat balance.

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