Scientists from Heriot-Watt University have secured new funding to investigate the thermodynamic behaviour of typical carbon capture, utilization, and storage (CCUS) fluids. This research is critical for the safe and efficient processing, transportation, and storage of these fluids.
Image Credit: Heriot-Watt University
The two-year project aims to improve thermodynamic models to predict the phase behaviour of CO2 rich mixtures, specifically focusing on volatile organic compounds (VOCs) as the impurities. The project outcomes will be pivotal in establishing optimum operational conditions throughout the CCUS chain as well as environmental compliance and proper CO2 storage.
In CCUS systems, VOCs are often found in the captured CO2 stream, primarily originating from the source of the CO2. VOCs include, for example, benzene, toluene, xylene (BTX), aldehydes (formaldehyde, acetaldehyde), and various hydrocarbons depending on the fuel source and capture conditions.
Jointly funded by TotalEnergies and Equinor, the new research project builds on Heriot-Watt University’s long-standing expertise in CCUS research. Since the institution’s first CCUS related joint industry project (JIP) in 2011, led by Professor Antonin Chapoy, a specialist research group has developed advanced laboratories and cutting-edge expertise in experimental and modelling studies of the thermophysical properties of CCUS fluids. Today, the group collaborates with more than ten major CCUS operators worldwide through consultancy and research projects.
Dr Pezhman Ahmadi, project lead, is from the specialist Hydrate, Flow Assurance and Phase Equilibria (HFAPE) research group at Heriot-Watt University. He emphasized the importance of this research:
"For safety and technical reasons, understanding the thermodynamic behaviour of a fluid is key to its successful processing, transportation, and storage. In CCUS projects, where the working fluid is usually a CO2 rich mixture, the presence of impurities significantly influences the behaviour of the fluid in comparison to a pure CO2 stream. While thermodynamic models for pure CO2 are reliable thanks to abundant experimental data, impure CO2 streams, which are common in industry, pose challenges due to limited data and deficiencies in existing models. This project focuses on VOCs as a critical category of impurities so we can better understand the influence of this type of impurities and address this data gap."
Heriot-Watt’s Professor Antonin Chapoy, project co-lead, has extensive experience in leading CCUS projects for the research group. He added: "Our modelling studies, underpinned by experimental capabilities and expertise, provide precise thermodynamic models that improve the safety, technical and economic aspects of CCUS operations. These models help reduce operational risks, such as hydrate or dry ice formation, and minimize costs while enhancing efficiency in the transportation and storage of CO2-rich fluids. Over the years, our work has supported major CCUS operators in achieving safer and more cost-effective operations."
The group's expertise was recently showcased through its involvement in the Northern Lights project, Norway's pioneering carbon storage initiative that opened in September 2024. The technical contributions made by this group of researchers were critical in ensuring the safe transportation and storage of CO2, with the team providing essential data on fluid behaviour under varying conditions.
Professor Chapoy continues: "Our contributions to CCS projects and our extensive expertise underscore the importance of understanding thermodynamic properties of CCUS fluids for the long-term success of decarbonization projects. With 14 years of focused research on this topic, our team continues to develop practical solutions to accelerate industry’s net-zero transition. This new project exemplifies our commitment to supporting global decarbonization efforts. We are grateful for the support of TotalEnergies and Equinor in driving this critical research forward."