Electrochemical high temperature processes

Concept sketches: First steps on the way to a process system.

GALACTICA: Experiments on SOC reactors with multiple, coupled SOC stacks (up to 150 kW).

Pressurized SOFC system: Stand-alone or virtually coupled with a gas turbine.

The "Electrochemical high-temperature processes" research group, researches process systems with electrochemical reactors operating at high temperatures. These include, in particular, reactors with solid oxide cells (SOCs), which can be used in electrolysis (SOE) as well as fuel cell mode (SOFC) and have the potentially highest possible efficiency. These high-temperature reactors can also be used for direct, electrochemical synthesis of high value products such as chemicals or fuels.

The close integration of simulation and experiments is vital for the operation of the research group. The flexible simulation tools, specially developed in the group, for modeling these reactors and systems, are also used on an interdisciplinary basis for process systems with AEL reactors (alkaline electrolysis), in the "Low temperature elctrolysis system" research group. Experimental investigations are carried out on several test benches to validate the simulations and characterize the reactors. The process engineering investigations include the integration of coupled, upstream and downstream processes (e.g. SOFC/battery systems for shipping, and Power to X systems for the defossilization of industry and aviation fuels).

Goals

• Development and research of strategies for the efficient and low-degradation operation of coupled, integrated electrolysis and fuel cell systems
• Upscaling of electrolysis systems into the 100 MW+ range and fuel cell systems into the 10 MW+ range.

To achieve the goals, the research group uses a combined research approach that closely links four scientific methods and instruments.

Scientific methods and instruments

• System concept development (simulation tool: CELESTE)
  Thermodynamic and reaction-kinetic simulations for energy and exergy analysis; development and comparison of process system configurations, with a focus on the integration of electrochemical reactors
• Transient process engineering system simulations (simulation tool: TEMPEST)
  Process simulations with a focus on electrochemical reactors for the development and research of operating strategies for overall, and sub-processes
• Experimental reactor investigations
  Pressurized and atmospheric investigations on SOC stacks (approx. 1–3 kW on the HORST test stand) and reactor modules with several, coupled SOC stacks (up to 150 kW on the GALACTICA test stand); parameterization and validation of CELESTE and TEMPEST models; testing of operating strategies from TEMPEST simulations
• Process engineering system level experiments
  Construction and operation of novel, complex process chains/sub-process chains (e-XPlore: pressurized SOC electrolysis system for direct coupling to downstream synthesis processes; hybrid power plant: virtually coupled hybrid power plant from pressurized SOFC and gas turbine)

Project examples

• Nautilus: Development of a drive unit consisting of SOFCs and batteries for cruise ships
• H2Mare PtX-Wind: Demonstration and investigation of offshore PtX systems

Infrastructure

• HORST
• GALACTICA
• e-XPlore
• Hybrid power plant