High-efficiency biomass gasifier SOFC systems with direct internal tar reforming

Removing biosyngas contaminants is crucial for the efficient and safe operation of biomass gasifier solid oxide fuel cells systems. Among the contaminants, tar might be considered an additional fuel if converted into H₂ and CO in a reformer or directly in the SOFC. However, no sufficient information is available on direct internal tar reforming. The knowledge gained during the 4-years project FlexiFuel-SOFC is presented. The aim of these studies was to determine the possibility to directly reform tar in the SOFC, and to assess the influence that other biosyngas contaminants (i.e., H₂S and HCl) can have on the process. Benzene can be regarded as fuel, while naphthalene as a contaminant. Also toluene can be reformed inside the SOFC, but HCl seems to affect the process. Acetic acid is completely converted inside SOFCs and its conversion appears not affected by H₂S. However, it causes carbon deposition, mainly in the inlet pipelines.