The effect of oxygen transport by catalytic bed materials in biomass gasification

摘要: Catalytic bed material is the most common primary measure to get a reasonable quality of the product gas in fluidized biomass gasifiers. The catalytic behavior cases related to some sort metal, often iron or nickel, which promote cracking tars. However, active material will also be oxidized and reduced and, hence, transport oxygen from rich the reducing areas gasifier. For an indirect gasifier this means that not only crack some tars, it burn part product thereby, reduce chemical efficiency, at same time as diluted with carbon dioxide. In work this effect has been investigated 2-4 MWfuel Chalmers, using silica sand bed material blended two different fractions(2 12 %) Ilmenite (iron-titanium oxide) active catalytic material, where higher fraction used, correspond capacity. The effect by materials commonly used Olivine. result shows between reactors the same order theoretical maximal Ilmenite, transport can significantly chemical efficiency process. effect will hidden; if mass balance process properly closed. Considering rapid oxidation reduction active further conclusion will also have significant direct provided be consumed subsequently contribute combustion instead char conversion; matter fact conversion char pushed towards much slower gasification reactions