Integrating biomass gasification with solid oxide fuel cells: Effect of real product gas tars, fluctuations and particulates on Ni-GDC anode

The aim of this work was to experimentally assess the feasibility of feeding real biomass product gas to solid oxide fuel cells (SOFC) for efficient and clean power production. The impact of tars on Ni-GDC anode was the main focus of the experiments. Planar SOFC membranes were operated at two gasification sites: (a) autothermal fixed-bed downdraft gasifier and (b) allothermal bubbling fluidized bed gasifier. In all cases the gas was hot-cleaned from particulates, HCl and H2S. SOFC membranes were tested up to one day on different product gas tar loads (0-3000 mg N m(-3)) with stable performance. SEM/EDS examination of the SOFCs revealed intact anodes; no carbon deposition or other impurities were detected. During testing on high fuel utilization conditions and high steam content, the SOFC lost performance due to anode nickel oxidation. In another extreme case where producer gas particulates reached the SOFC, SEM examination identified secondary tubular shaped carbon structures formed inside the functional layer of the anode. (c) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.