Quality of producer gas from different biogenous fuels

Nowadays gasification of untreated wood chips can be considered as state-of-the-art, successfully demonstrated at an industrial scale in various plants throughout Europe, e.g. Harboore in Denmark and Güssing Austria. In comparison, the experience with other/alternative biomass fuels is limited. Scientific research is now focusing on remedying this situation. This work investigates the gasification of different fuels of Irish origin in comparison to that of wood. To that end, a pilot scale bubbling fluidised bed gasifier was built at Fraunhofer UMSICHT. The fuels to be gasified are wood chips, as reference, willow from short rotation coppice, miscanthus, straw and peat. All fuels have, except straw due to harvesting windows, been processed for adaptability with the feeding system. For these sourced fuels, thermodynamic equilibrium studies were conducted to calculate the operating temperatures and main gas compositions to be expected in the pilot plant. The results indicate that the plant can be operated at maximum efficiency without agglomeration problems while producing a gas of sufficient heating value for a gas engine. The maximum cold gas efficiency obtainable is noted as similar for all fuels. As such the choice of biomass fuel can be based primarily on availability.