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

Abstract 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 H 2 S. 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.

[1]  N. Woudstra,et al.  Biosyngas Utilization in Solid Oxide Fuel Cells With Ni∕GDC Anodes , 2006 .

[2]  Phillip N. Hutton,et al.  Carbon deposition in an SOFC fueled by tar-laden biomass gas: a thermodynamic analysis , 2005 .

[3]  M. Fowler,et al.  Experimental and modeling study of solid oxide fuel cell operating with syngas fuel , 2006 .

[4]  Ta-Jen Huang,et al.  Methane decomposition and self de-coking over gadolinia-doped ceria-supported Ni catalysts , 2007 .

[5]  SMALL SCALE HOT GAS CLEANING DEVICE FOR SOFC UTILISATION OF WOODY BIOMASS PRODUCT GAS , 2007 .

[6]  R. Gemmen,et al.  The effect of coal syngas containing HCl on the performance of solid oxide fuel cells: Investigations into the effect of operational temperature and HCl concentration , 2007 .

[7]  Daniel Favrat,et al.  Simulation of SOFC stack and repeat elements including interconnect degradation and anode reoxidation risk , 2006 .

[8]  Christopher S. Johnson,et al.  Sulfur-tolerant anode materials for solid oxide fuel cell application , 2007 .

[9]  Ta-Jen Huang,et al.  Factors in forming CO and CO2 over a cermet of Ni-gadolinia-doped ceria with relation to direct methane SOFCs , 2006 .

[10]  François Maréchal,et al.  Generalized model of planar SOFC repeat element for design optimization , 2004 .

[11]  Randall Gemmen,et al.  The effect of coal syngas containing AsH3 on the performance of SOFCs: Investigations into the effect of operational temperature, current density and AsH3 concentration , 2007 .

[12]  Wei Wang,et al.  GDC-impregnated Ni anodes for direct utilization of methane in solid oxide fuel cells , 2006 .

[13]  U. Hohenwarter,et al.  High temperature electrolyte supported Ni-GDC/YSZ/LSM SOFC operation on two-stage Viking gasifier product gas , 2007 .

[14]  Claes Brage,et al.  Guideline for sampling and analysis of tar and particles in biomass producer gases , 2008 .

[15]  Yves U. Idzerda,et al.  Mechanism for SOFC anode degradation from hydrogen sulfide exposure , 2008 .

[16]  Nigel P. Brandon,et al.  The impact of wood-derived gasification gases on Ni-CGO anodes in intermediate temperature solid oxide fuel cells , 2004 .

[17]  K. Kendall,et al.  High temperature solid oxide fuel cells : fundamentals, design and applicatons , 2003 .

[18]  T. A. Milne,et al.  Biomass Gasifier "Tars": Their Nature, Formation, and Conversion , 1998 .