Vorrichtung und Verfahren zur Erzeugung eines teerfreien Schwachgases durch Vergasung von Biomasse

WO2005113732 A UPAB: 20051222 NOVELTY - Gasifier comprises an upper feed drying and pyrolysis zone (1) with a pyrolysis gas withdrawal system (6), a middle reduction zone (2), a lower char gasification zone (3) with a fuel gas withdrawal system (8), a gas mixing system (5) connected to the pyrolysis gas and fuel gas withdrawal systems, and a gas supply system (7) for supplying the mixed gas to the reduction zone. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a gasification process comprising drying and pyrolyzing a feed in a drying and pyrolysis zone (1), catalytically cracking tars and reducing carbon in a reduction zone (2) beneath zone (1), gasifying char in a char gasification zone (3) beneath zone (2), withdrawing pyrolysis gas streams from zones (1) and (3), mixing the gas streams and passing the mixture to zone (2). USE - Gasifier for converting a feed material, especially biomass, into a tar-free fuel gas, e.g. for use in a gas engine. ADVANTAGE - The gasifier produces a hydrogen- and carbon monoxide (CO)-rich gas with a tar content of no more than 50 mg/Nm3 that requires neither catalytic treatment nor scrubbing