Periodic Reporting for period 1 - SOMMER (Solar-Based Membrane Reactor For Syngas Production)
Période du rapport: 2023-11-01 au 2025-04-30
1. CASE I (1500 °C, solar-driven): Various ceramic membrane materials were evaluated, with Yttria-Stabilized Zirconia (YSZ) and Gadolinium-Doped Ceria (GDC) emerging as the most suitable due to their thermochemical stability. YSZ was found compatible with both conventional processing methods and manufacturability via both slip casting and additive manufacturing (3D printing), while 3D printing of GDC was not feasible. Corrugated membrane geometries were successfully printed and tested; however, scalability remains a challenge, this prompted the exploration of hybrid assembly solutions.
2. CASE II (900 °C, biogas-supported): Strontium Titanium Ferrite (STF) and GDC were selected for their excellent oxygen permeation and catalytic potential. STF-based asymmetric membranes were fabricated using slip casting and extrusion methods, with extrusion being further developed for the required reactor-scale geometries.
High-temperature electrical conductivity measurements and mechanical creep behavior tests were performed on candidate materials, addressing long-term stability and mechanical integrity under extreme conditions.
New membrane reactor components and sealing techniques were validated. A custom-built test rig was developed for kinetic and performance evaluations, supporting both membrane disc and tube formats under simulated CASE I and CASE II conditions.
Significant progress was made in defining the operating conditions for the solar membrane reactor and outlining the downstream process for methanol synthesis. Efforts included optimizing the reactor for converting H2O and CO2 into syngas and designing the downstream process based on the expected syngas composition.
Advanced multi-physics simulations, including thermodynamic and CFD models, guided reactor design and material selection. Simulation work identified the importance of low oxygen partial pressures, sweep gas flow optimization, and membrane geometry in achieving high conversion rates. Reactor design iterations ensured compatibility with membrane properties and thermal constraints.
Optical and thermal simulations of solar flux distribution informed the design of the cavity receiver for solar irradiation, optimizing temperature homogeneity along the membrane.
Initial reactor designs have been completed and optimized for both operational cases, ensuring high-efficiency performance under solar and biogas-assisted conditions.
- Identification and experimental validation of doped YSZ and STF as leading candidates for high-temperature membrane reactors.
- Development of printable ceramic structures and hybrid joining techniques for scalable reactor integration.
- Unique experimental data on high-temperature conductivity (up to 1500 °C) and mechanical creep in doped ceramics, which are scarce in current literature.
- Creation of a robust test infrastructure for evaluating mixed-conducting membranes under realistic conditions to identify rate-limiting or synergistic effects. Commissioning of the test unit is currently underway.
- Coupled reactor-process modelling linking upstream membrane performance with downstream syngas-to-methanol conversion, supporting full system integration.
- Optical and thermal validation of cavity receiver concepts for concentrated solar input, enabling uniform heating critical for CASE I.
- Development of uniquely scaled-up solar membrane reactor designs to achieve optimal conversion.