Modeling of a SOFC Fueled by Methane:Anode Barrier to Allow Gradual Internal Reforming Without Coking

Abstract

Natural gas appears to be a highly attractive fuel for solid oxide fuel cells. To avoid the cooling occurring in direct internal reforming, gradual internal reforming (GIR) can be used. GIR is based on local coupling between steam reforming and H oxidn. The steam required for the reforming reaction is obtained from H oxidn. on the anode side. Previous studies demonstrated that the cooling effect has disappeared. However, with GIR, the risk of C formation is greater. To deal with this issue, a different cell configuration was studied. This configuration combines a catalyst layer with a cermet anode, allowing GIR without coking. The study comprised simulations, using the CFD Research Corporation software package, of the behavior of a tubular SOFC when using GIR. A thermodn. study based on partial pressure distributions within the cell was also carried out to understand C formation. A parametric anal. of the reforming rate and the thickness of the layer were then performed. The simulations indicate that the risk of C deposition is decreased if the configuration used for the catalyst layer of 900 μm and at a reforming rate in the catalyst only 10 times higher than the reforming rate in Ni. [on SciFinder(R)]