Catalytic partial oxidation of methane in a molten carbonate fuel cell

Abstract

The aim of the present paper is to evaluate the thermodynamic yields for a direct internal methane catalytic partial oxidation (CPOX) in a molten carbonate fuel cell (MCFC), operating with or without a cogeneration bottoming cycle. The influence of several operating parameters on the mass and energy balances of a 10 kW power plant has been investigated by using a mathematical model. The temperature, the methane inlet flow, the fuel utilisation coefficient, the electrical power and the useful heat fraction have been found to be relevant parameters to investigate the behaviour of the system. The examination of the results shows that the highest generated electrical power corresponds to a fuel utilisation coefficient of 80%, with a very appreciable methane conversion. The electrical efficiency obtained for the examined system is lower than that from a direct methane steam reforming monocell (DIR MCFC), but the exhaust gas composition seems to be usefully adoptable for the production of organic compounds. The overall system efficiency strongly improves if the thermal energy available is fully or partially recovered. In these cases, the theoretical energy efficiency ranges from 100% to 54.9%. All the evidence indicates that this system appears very flexible for applications in plants for the production of syngas for CH3 OH or NH3 sintesys where the electricity is a by-product. These interesting opportunities require a further investigation on some detrimental aspects that could affect the methane CPOX fuelled MCFC. 1999 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.