Oxygen-blown entrained flow gasification (EFG) of biomass is a promising technology for further reducing CO2-emissions in power production (e.g. via IGCC plants or fuel cells) or chemical/fuel production (e.g. MeOH or Fischer-Tropsch synthesis). It produces a high quality synthesis gas with a low tar content while achieving high carbon conversions and enabling simple pressurized operation. Although biomass is a non-volatile energy source and gasification is better suited for stationary operation, the future energy system requires biomass gasification plants to behave flexible on load and fuel due to increasing shares of wind and solar power and varying fuel properties of biomass. Key for an efficient EFG process is a stable and optimized flame aligned with the fuel properties and the operational conditions. Hence, a flexible operation of an EFG demands the flame to adjust to fluctuating process conditions. In this study, a new additively manufactured gasification burner for small scales developed at the Chair of Energy Systems at Technical University of Munich is commissioned and tested in an autothermal EFG test plant. With this burner it is possible to vary the gasifying agents’ outlet area and to in-situ adjust the agents’ swirl between 0 and 60 degrees for examining the influence for different loads and fuels on efficiency and stability of the process. It also holds a new way of distributing the pulverized biomass in an efficient way into the gasifying agents to prevent clogging at small geometries. The test plant is a pilot-scale industrial-like EFG with a thermal input of 100-200 kW that can be operated with preheated air, oxygen, steam and carbon dioxide up to 5 barg. Particles as well as gas can be withdrawn, while gas compositions can be measured with gas chromatography, online gas analysis (NDIR, TCD, paramagnetic sensor) and solid phase extraction for tar analysis. Particles can be investigated in respect to their composition, particle size distribution, particle density and surface development. The test plant uses a CCD-camera for control of the flame behaviour. In this work hydrothermal carbonized green cut (HCG) with a high ash content is used for the commissioning of the new burner. The HCG is gasified with pure oxygen and with oxygen/steam mixture. First results, including flame image analysis as well as gas compositions, carbon conversions and cold gas efficiencies (up to 70 %) based on N2-tracer, show a well operating burner superior to the previous design with first indications towards the influence of the swirl on the gasification efficiency.
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