PETR 96 |
| The use of biogas as an energy source in polymer electrolyte membrane fuel cells (PEMFC) with combined heat and power generation provides a clean and reliable option to replace conventional power generation with fossil fuels. From the point of view of energy and ecological policy, it has the advantage both of being a comparatively cost effective domestic regenerative energy source, as well as being a technology that unites high electrical efficiency with low pollution emission. The investigative experiments carried out confirm the fundamental suitability of cogeneration from Biogas with a modified fuel cell system for residential energy supply. The fuel cell system consists of the PEM fuel cell unit and a steam reformer with two stage shift converter and selective oxidation and is supplied with biogas from two solid state fermenters. The substrate used is a mixture of manure and corn silage. By adding manufactured gases, the methane content of the biogas is varied. Biogas with a methane content of about 60% is generated by solid state anaerobic digestion of cattle manure and corn silage. Biogas processing in a steam reformer results in a reformate gas with a hydrogen purity of more than 50% which is sufficient for an efficient and stable operation of a PEM fuel cell stack. The hydrogen concentration is dependent on the quality of biogas. The operation of the fuel cell at a current density of 0.2 A/cm2 offers a cell efficiency of more than 58%. The influence of the biogas methane concentration on the cell efficiency is slight in the range of low power density needed to achieve high efficiency. |
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Symposium on Clean Fuels from Biomass
1:30 PM-5:15 PM, Tuesday, 12 September 2006 Palace -- Twin Peaks North, Oral
Division of Petroleum Chemistry |