In-bed catalytic tar reduction in a dual fluidized bed biomass steam gasifier

A nickel-enriched catalytic bed material was tested for tar reduction in a 100 kW(th) dual fluidized bed biomass steam gasifier. Gas composition and tar content were measured after the reactor and compared with data from gasification tests without a catalytic bed material. H-2, CO, CO2, and CH4 contents in the product gas, as well as tar conversion rates, are reported for different amounts of catalytic active bed material and different operating conditions. Water conversions, gas yields, and lower heating values were calculated. The catalyst showed no noticeable deactivation in two tests of 30 and 45 h. These results obtained at the pilot scale represent an important intermediate step in preparing the technical breakthrough of dual fluidized bed biomass steam gasification.