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Biomass is one of the renewable and potentially sustainable energy sources and has many possible applications varying from heat generation to the production of advanced secondary energy carriers. The latter option would allow mobile services like the transportation sector to reduce its dependency on the fossil fuel supply. This article reviews the state-of-the-art of the fluidization technology applied for the gasification of biomass aimed at the production of gas for subsequent synthesis of the liquid energy carriers via, e.g., the Fischer-Tropsch process. It discusses the advantages of the gasification technology over combustion, considers the size of the conversion plant in view of the local biomass availability, assesses the pros and cons of different gasifier types in view of the application of the product gas. Subsequently the article focuses on the fluidized bed technology to discuss the main process parameters and their influence on the product composition and the operability of the gasifier. Finally a synthesis process (FT) is introduced shortly to illustrate the necessary gas cleaning steps in view of the purity requirements for the FT feed gas.

High energy prices and an established awareness of the anthropogenic origin of global warming are stimulating markets and policymakers to move toward a much higher utilization of biomass fuels for energy conversion. In order to develop efficient processes, though, much research is still needed to characterize the behavior of such alternative fuels. In this paper the pyrolysis of some agro-residues, abundant in Europe, was studied in a TG-FTIR setup. In order to remove from the samples the alkali metals and Cl which are detrimental for process operation, causing slagging, fouling, and loss of fluidization, a water leaching pretreatment was applied to all the samples. The thermogravimetric curve of wheat straw showed a singular peak at 324 °C and a residue of 21.6 wt % ar. The leaching pretreatment increased the temperature of reaction up to 355 °C and the weight loss to 83.3 wt % ar. The olive residue sample also showed an increase in reacting temperature and volatile release. The peach sample, probably due to its different composition, reacted over two very distinct peaks at 287 and 359 °C. The leaching procedure did not affect this sample on the temperatures of reaction, while it slightly increased the amount of volatiles released. A distributed activation energy method (DAEM) was used to retrieve kinetic parameters from the measurements. When using a discrete distribution with a fixed pre-exponential factor of 2.2 × 1013 [s−1], the main reaction path for wheat straw and olive residue appeared to be at 176 kJ/mol, while for the leached samples and for the peach stones sample it appeared at 184 kJ/mol. The leaching pretreatment removed a high percentage of mineral inclusions in the samples, mostly in the forms of KCl and NaCl. This increased the temperature at which the samples decomposed, increased the released volatiles, and slightly increased the reaction rate.