How CO2 is turned into polyurethanes in the BECCU concept?
The BECCU project is developing a new value chain from bioenergy production to sustainable materials by utilizing carbon dioxide emissions and clean hydrogen. VTT has studied a process where 100 % of polyol carbon is originating from carbon dioxide. In the BECCU concept, all begins from the efficient utilization of biomass feedstock such as agrobiomass as seen in the figure below. All of the stages of the concept will be demonstrated experimentally in the BECCU project in cooperation with project partners.
The polyol production is proceed from the captured CO2 and H2 either from electrolysis or from industrial side-streams. The polyol manufacturing process is based on the production of olefins through reverse water-gas shift (rWGS) and Fischer-Tropsch (FT) reaction steps. Produced olefins are further converted to epoxides through oxidation reactions by peroxides and epoxides are polymerized together with CO2 to obtain polyols. This is an ultimate novelty of the developed concept in the project.
Polyols and polyisocyanates are the main building blocks of polyurethanes. Polycarbonate polyols are applied in polyurethane applications where high performance including high hydrolytic, thermal and UV stability is required. The most common usages are very high-performance applications in coatings, adhesives and elastomers. Another type of polyols to be studied in the BECCU project is polyether polyols. They are most common polyols with 70 % global market share. All the target end-products represent high potential both in terms of CCU and economic performance.
As seen, a number of valuable by-products such as transportation fuels are produced in the value chain of the targeted polyurethane end-products. These are taken into account in the techno-economic assessment of the concept. Also comparative P2X-concepts for CO2 utilization will also be evaluated. This enables comprehensive analysis of the concept related to optional CCU approaches. Selected comparative P2X-concepts for the techno-economic analysis are:
- SNG: hydrogen boosting in biogas production site
- Methanol: CO2 use in methanol synthesis for selected industrial environment
- Ash-treatment: CO2-based solid aggregates within bio-CHP production
Techno-economic assessment will be performed for different process configurations of integrated BECCU-concept for heat, power, fuels and chemicals production. Based on techno-economic feasibility and LCA of the value chain, business opportunities, future demonstrations and impact of policy framework will be evaluated together with our industrial partners.