approach. The first stage consists of multiple decentralized pyrolysis
plants to liquefy the biomass collected from a radius of about 30 km
around each pyrolysis plant. The produced slurry offers a tenfold
increased volumetric energy density and allows economical transportation over long distances to the centralized large scale gasification
and synthesis plant [11]. For economic reasons, the capacity of the
gasification and synthesis plant should be as large as possible in order
to produce more efficiently and cost-effectively [12]. After cleaning
and conditioning, the syngas can be used to synthesize fuels or
chemicals by different pathways. Under discussion are e.g. Fisher–
Tropsch synthesis to diesel, gasoline and waxes, dimethyl ether or
methanol synthesis. The first steps of a BtL process chain are crucial
for the competitiveness. While the tail-end steps do not differ to a
large extent between XtL technologies, the starting steps need to
consider the biomass characteristics in the production of syngas of a
specified quality. In an earlier study the authors assessed the pyrolysis
step. Therefore the focus of this contribution is the assessment of the
gasification of slurry produced in fast pyrolysis plants as a process step
in BtL fuel and chemicals production as presented in Fig. 1.