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TY - THES AU - Kopsch, Markus TI - Inorganic trace substances in a sorption enhanced gasification process and their removal PB - Rheinisch-Westfälische Technische Hochschule Aachen VL - Dissertation CY - Aachen M1 - RWTH-2025-02830 SP - 1 Online-Ressource : Illustrationen PY - 2024 N1 - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2025 N1 - Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2024 AB - The energy supply by biomass, especially by biomass residues, currently enjoys high acceptance among the German population due to the energy crisis. A process that enables the use of biomass residues for power generation is the Ca-looping gasification process proposed in the European GICO-Project. This process requires a hot gas conditioning (HGC) unit for a gasifier and a calciner to remove inorganic trace substances. To this end, extensive equilibrium calculations with FactSage were conducted for the GICO gasifier (650 °C), and calciner (920 °C), showing that aluminosilicates, Sr-, and Ba-based sorbents could reduce the alkali, respectively sour gas (H2S/SO2, HCl) concentration to sub ppmv levels. Condensation calculations reveal the need for temperature-resistant H2S sorbents since conventional ones, e.g. Zn2TiO4, tend to evaporate, leading to the condensation of unwanted salts, and oxides. Since the release behavior of inorganic trace species and their adsorptive removal under gasification-like conditions between 650 °C and 700 °C has hardly been investigated, the experimental focus of this work is placed on the gasifier operating at 650 °C. The release behavior of inorganic trace substances from raw, water-leached, and hydrochar biomass samples was investigated using molecular beam mass spectrometry (MBMS). The sorption capacity of aluminosilicates, alkaline earth, and rare earths-based sorbents was determined by mass spectrometry (MS) in fixed bed lab-scale investigations. The investigations showed that aluminosilicates are suitable for alkali removal. Furthermore, the results indicate that Ca-stabilized Sr- and Ba-sorbents reduce H2S sufficiently. In both cases, concentrations could be brought below 1 ppmv. Compatibility experiments between filter material (Al- and Ca-Mg-silicate fibers) and sorbents were conducted to investigate the possibility of integrating the sorbents into the filter candles in order to allow a more compact HGC design. Since the Zn-sorbents are not reacting with the filter candle material, they can be integrated into the filter candle. However, aluminum- and silicate-phases are formed when using Sr- and Ba-based sorbents leading to potential risks such as the formation of cracks. Based on the modeling calculations, release, sorption, and compatibility experiments, chemical HGC concepts for different sorbents are proposed. LB - PUB:(DE-HGF)11 DO - DOI:10.18154/RWTH-2025-02830 UR - https://publications.rwth-aachen.de/record/1006938 ER -