In cooperation with Uniper SE, the DLR Institute for Future Fuels has conducted a year-long study to determine which options exist for CO2 utilization in North Rhine-Westphalia (NRW). Particular attention was paid to the region Rhenish lignite mining area, which is still strongly characterized by opencast lignite mining and which is facing specific challenges from structural change. The Rhenish lignite mining area comprises the area between the major cities of Düsseldorf, Bonn and Aachen.
Based on a site analysis, the authors of the study investigated which industrial products are particularly suitable for using carbon dioxide (CO2) instead of fossil carbon as a carbon source in production processes, so-called "carbon capture and utilization" (CCU).
When the CO2 is extracted from industrial exhaust or the atmosphere, it enables the transition to a carbon cycle that avoids the need to exploit new fossil carbon sources. The study divided the processes into chemicals, fuels and proteins/biomass. A detailed set of criteria was used to evaluate and rank the processes. In doing so, the authors considered technical, ecological, economic, but also infrastructure-relevant aspects in order to obtain as comprehensive a picture as possible of the CCU options. Using a selected chemical park as an example, they compared the economic viability of the best candidates. Different plant sizes as well as varying costs for production and raw materials were considered for the analysis of an exemplary site.
Current regulatory frameworks provide little to no support for economic CO2-based production of chemicals or fuels. However, the analysis shows that especially the production of formic acid and acetic acid are promising CCU alternatives and appear feasible in NRW. In the area of fuels, the CO2-based production of kerosene scored best. However, this first requires an expansion of renewable energies for green hydrogen production or hydrogen infrastructure.
The CCU-Akzelerator project was partially funded by the state of NRW, approved by Projektträger Jülich, in the framework of IN4climate.NRW.
The results of the study are available to the public as a report and can be downloaded here.