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천연가스의 수증기-이산화탄소 복합개질용 촉매 충진 반응기의 코킹 회피 운전을 위한 모사

Simulation for Possible Coke-Free Operation of a Packed Catalyst Bed Reactor in the Steam-CO2 Reforming of Natural Gas

  • 이득기 (광주대학교 소방행정학과) ;
  • 이상수 (광주대학교 토목공학과) ;
  • 서동주 (한국에너지기술연구원 수소연료전지연구단) ;
  • 윤왕래 (한국에너지기술연구원 수소연료전지연구단)
  • LEE, DEUK KI (Dept. of Fire Safety, Gwangju University) ;
  • LEE, SANG SOO (Dept. of Civil Engineering, Gwangju University) ;
  • SEO, DONG JOO (Hydrogen and Fuel Cell Department, Korea Institute of Energy Research) ;
  • YOON, WANG LAI (Hydrogen and Fuel Cell Department, Korea Institute of Energy Research)
  • 투고 : 2015.09.08
  • 심사 : 2015.10.30
  • 발행 : 2015.10.30

초록

A tubular packed bed reactor for the steam-$CO_2$ combined reforming of natural gas to produce the synthesis gas of a target $H_2/CO$ ratio 2.0 was simulated. The effects of the reactor dimension, the feed gas composition, and the gas feeding temperature upon the possibility of coke formation across the catalyst bed were investigated. For this purpose, 2-dimensional heterogeneous reactor model was used to determine the local gas concentrations and temperatures over the catalyst bed. The thermodynamic potential distribution of coke formation was determined by comparing the extent of reaction with the equilibrium constant given by the reaction, $CH_4+2CO{\Leftrightarrow}3C+2H_2O$. The simulation showed that catalysts packed in the central region nearer the entrance of the reactor were more prone to coking because of the regional characteristics of lower temperature, lower concentration of $H_2O$, and higher concentration of CO. With the higher feeding temperature, the feed gas composition of the increased $H_2O$ and correspondingly decreased $CO_2$, or the decrease in the reactor diameter, the volume fraction of the catalyst bed subsequent to coking could be diminished. Throughout the simulation, reactor dimension and reaction condition for coking-free operation were suggested.

키워드

참고문헌

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