The bioliq process is to produce synthetic bio-fuels from biomass including agriculture residues. The process is currently under development and testing at pilot scale at KIT. It involves production of biomass slurry called biosyncrude, its gasification at a high pressure, and subsequent cleaning/conditioning of the syngas and gasoline synthesis. An essential element of the process is the entrained flow gasifier which is designed for a 5 MW_(thermal) input and is to be operated at a nominal pressure of 40 and 80 bar, respectively. The paper presents R&D work carried out at KIT and TUC respectively, concerning data acquisition on slurry atomization, entrained flow gasification and CFD-based numerical simulations which have been carried out in the design phase of the oxygen-blown gasifier. The primary questions are concerned with dimensioning of the reactor (diameter, length, surface/volume ratio), the issue which is directly linked to the burner (set of injectors at the top of the gasifier) design. The essential criterion in assessing the design options is the chemical composition of the syngas, the conversion rate of the fuel as well as the gasifier exit temperature since all parameters affect the cold gas efficiency. The gasification process is to operate with a complete burnout of bio-coke particles and this issue requires special attention to fuel preparation and atomization. The gasifier is designed to operate in slagging mode so that a molten layer of slag flows along the gasifier walls. To secure a continuous slag flow, without slag accumulation and build-up, appropriate heat transfer conditions must prevail at the gasifier walls. Thus, conjugated heat transfer through the slag layer and the refractory, with radiative and convective contribution at the gasifier inside, has been examined. First results on the operation of the 5 MW entrained flow gasifier are reported.
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