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A test campaign was carried out to generate renewable hydrogen based on wood gas derived from the commercial biomass steam gasification plant in Oberwart, Austria. The implemented process consisted of four operation units: (I) catalyzed water−gas shift (WGS) reaction, (II) gas drying and cleaning in a wet scrubber, (III) hydrogen purification by pressure swing adsorption, and (IV) use of the generated biohydrogen (BioH 2 ) in a proton exchange membrane (PEM) fuel cell. For almost 250 h, a reliable and continuous operation was achieved. A total of 560 (L n dry basis (db) )/h of wood gas were extracted to produce 280 (L n db )/h of BioH 2 with a purity of 99.97 vol % db . The catalyzed WGS reaction enabled a hydrogen recovery of 128% (nḂ ioH 2 )/(nḢ 2 ,wood gas ) over the whole process chain. An extensive chemical analysis of the main gas components and trace components (sulfur, C x H y , and ammonia) was carried out. No PEM fuel cell poisons were measured in the generated BioH 2 . The only detectable impurities in the product were 0.02 vol % db of O 2 and 0.01 vol % db of N 2 .

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In many processes proposed for biorefineries, recycling procedures, and industrial or agricultural production processes, residue is generated which could be further transformed by thermochemical conversion via gasification. The technology of dual fluidized bed steam gasification is capable of producing a valuable product gas out of such residue. The generated nitrogen-free product gas can be used for heat and power production and is suitable for separating gases (e.g. hydrogen). However, if the product gas is cleaned, its use as syngas is more beneficial for manufacturing renewable chemical substances, like synthetic natural gas, methanol, Fischer-Tropsch liquids, or mixed alcohols. This paper presents the results of experimental research from gasification test runs of different biogenic fuels, carried out with an advanced 100 kW pilot plant over the last 5 years at TU Wien. The focus is to provide an overview of measured results validated by mass and energy balances and to present key calculated performance indicating key figures of the test runs. In this way, the influence of various operational parameters and the composition of the product gas are evaluated. The presented results form the basis for the proper design of suitable gas-cleaning equipment. Subsequently, the clean syngas is available for several synthesis applications in future biorefineries.

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Biomass energy conversion is a reliable way to produce energy and chemical products if compared with other renewable sources such as wind, solar and wave which have intermittent nature. Amongst different methods of converting biomass to energy, the thermo-chemical process of steam gasification is an outstanding way, since it enables a subsequent polygeneration process that can lead to production of heat, electricity, synthetic natural gas and synthetic chemicals such as methanol, Fischer-Tropsch diesel, gasoline and kerosene. The modelling of biomass gasification enables the optimization of the process designs, but it is a challenge due to its high complexity. Here, a new approach is used to simulate a 100 kW dual fluidized bed gasifier. Detailed pyrolysis modelling is a key factor of this approach and enables more accurate results. The results have been validated by experiments conducted with softwood pellets as fuel and fresh olivine sand as bed material. The impact of the gasifier temperature variation on the final product gas composition is measured in the experiments and implemented in the simulation to have a better insight on the pyrolysis process, the char heterogeneous reactions as well as the deviation from equilibrium of the water gas-shift reaction.

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