of CO2 per day are used as feedstock.
Utilising carbon dioxide (CO2) as a raw material and thereby avoiding CO2 emissions is the core concept behind the ALIGN-CCUS and TAKE-OFF projects. Whereas under the pilot project known as ALIGN-CCUS, which was completed in November, RWE Power, Mitsubishi Power Europe and Asahi Kasei aimed to produce dimethyl ether, DME for short, from captured CO2, electricity and water, the follow-up project known as TAKE-OFF, starting in 2021, goes a stage further: here, they plan to produce efficient aviation fuel from DME by adding a further step to the process.
Thirty companies, organisations and research institutes from five European countries were involved in ALIGN-CCUS. The acronym ALIGN-CCUS stands for: Accelerating Low Carbon Industrial Growth through Carbon Capture, Usage and Storage. The Power-to-X research facility in Niederaussem produces DME from captured CO2, electricity and water, and the commodity can also serve as a feedstock for the chemical industry and as a synthetic substitute for diesel. The TAKE-OFF project is developing the production of synthetic renewable aviation fuel from CO2 and H2. Two process routes being studied use DME for this purpose, and in future will also use methanol, which are produced in Niederaussem.
The new process makes it possible to synthesise DME in a single process step in the synthesis facility designed and built by Mitsubishi Power Europe, using a monolithic reactor and a newly developed catalyst. So far, methanol has initially been produced from CO2 and hydrogen and then DME has been created in a second stage of the process. The starting point for DME synthesis is CO2 captured from the flue gas of the Niederaussem lignite-fired power plant by means of amine scrubbing. The plant is designed to capture a total of around 7.2 tonnes of CO2 per day. Up to 180 kilograms of CO2 per day are reacting with 22 kilograms of hydrogen to create DME. The hydrogen for the DME synthesis is produced on site by means of a highly efficient alkaline electrolysis system made by Asahi Kasei. The new synthesis facility can thus produce up to 50 kilograms of crude DME per day. The CO2 that is not used for CCUS projects in the Innovation Centre in Niederaussem is made available to Forschungszentrum Jülich for crop research.
“ALIGN-CCUS and TAKE-OFF represent important development phases as regards setting up a demonstration plant for cross-sectoral reduction of greenhouse gas emissions in the future.”
Tilman Bechthold, Head of Research and Development at RWE Power
DME and methanol are energy carriers that can be stored and transported. Due to their high energy density they can be used firstly as a long-term chemical form of storage for electricity and secondly also as synthetic fuel, if no lower-carbon alternative is available. In addition, DME and methanol are also chemical feedstocks for a wide range of other applications, such as precursors of compounds that are used in cosmetics, detergents, dyes or medicines, or as intermediate products for the production of aviation fuel.
Even after decommissioning fossil fuel power plants, there will still be unavoidable sources of CO2 from various industrial processes. ALIGN-CCUS and TAKE-OFF demonstrate a technology by means of which CO2 can be used as a raw material and, in combination with hydrogen, can replace fossil-based raw materials. Basic chemicals or fuels based on DME and methanol, which are produced in this way from captured CO2 and prospectively from green hydrogen, will make it possible to store and transport energy in chemical form, thus serving to couple the sectors and contributing to the success of the energy transition.