Abstract
To establish an efficient biomass gasification process a new concept of a circulating fluidized bed system with three reactors i.e., a low temperature steam gasifier for wood chips and a partial combustion steam gasifier (for carbon deposited on bed material and char) and a regenerator has been proposed. In this process, clay-derived porous catalysts having a capacity to capture tar-like components are applied for bed material.
To obtain fundamental data for conceptual design tar absorption capacity and a catalytic effect of bed material was experimentally determined by using a laboratory scale batch reactor (i.d.=43mm). Gas production and tar holding effect were quantified by using a laboratory scale fluidized bed system. The increase of gas production was observed especially in low cat/feed ratio (cat/feed (kg/kg) < 100). Furthermore, activated clay held twice or more amount of carbonaceous materials in the particle than the porous silica did resulting in the reduction of high boiling point tar.
