Production of hydrogen-rich gas by a low temperature plasma reactor

  • Young Chun, BK21 Team for Hydrogen Production·Department Environmental Engineering, Chosun University, Korea
  • Seong Kim, BK21 Team for Hydrogen Production·Department Environmental Engineering, Chosun University, Korea
  • Yun Yang, BK21 Team for Hydrogen Production·Department Environmental Engineering, Chosun University, Korea

    • Studies on the production of hydrogen rich gas from the hydrocarbon fuels, have been focused on the reforming processes of steam, CO2, catalyst and partial oxidation. The steam reforming requires the supply of high temperature and high pressure steam, and the carbon dioxide and catalyst reforming methods also require lots of externally supplied energies as an endothermic reaction. A partial oxidation reaction represents an exothermic reaction compared to that of steam and CO2 reforming reactions. But, production rate of hydrogen is less than other reforming caused by N2 in air.
    This study designed a reforming system that has a type of gliding are (so called glidArc) electrode using low temperature plasma, and performed a study on optimum conditions in the production of hydrogen using methane with steam by combining it with a catalyst reactor. It consists of the glidarc plasma reformer, a preheating system, a power supply, a gas supply line and a measurement/analysis line. In a glidarc plasma reformer, 3 glidarc shaped electrodes are connected 120 degrees apart with ceramic plate and the distance between the discharge electrodes is 3mm.
    The input power was fixed as 1.3 kW. The amount of methane flow was fixed as 2 L/min when the ratio of S/C (steam to carbon ratio) was controlled by 0.45~6.2. Therefore, the experiment was conducted at a condition that exceeds the ratio of S/C more than 3. The results were compared according to the application of Ru catalysts, with using a catalyst or without a catalyst. The operation temperature of a Ru catalyst reactor was 672?.
    The optimum condition and the results are as follows; The condition of S/C was selected as 3. The hydrogen and carbon monoxide was 54% and 17.8%, respectively. And the CH4 conversion rate and specific energy requirement were 81.6% and 35.2%. Above results were the case of using an Ru catalyst. But when without the catalyst, The hydrogen and carbon monoxide was 39% and 16%, and specific energy requirement were 33%. This result showed that presence of Ru catalyst was more effective for producing the hydrogen rich gas.

    Acknowledgements
    This research was conducted with a grant from the Korea Science Foundation (No. R01-2006-000-10355-0) with funds provided by the Ministry of Science and Technology in 2006.

    References
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