Cryogenic CO2 capture for gas phase separation

Growing concern about climate change and rising carbon dioxide levels in the atmosphere has increased the need for effective carbon capture technologies. This study focuses on the development of a novel three-stage cryogenic carbon capture process, de-signed to obtain liquid CO2 as the final product. In this process, CO₂ is captured in a packed bed column through phase change, by cooling the flue gas until CO₂ reaches its solid–gas equilibrium temperature. Under these conditions, CO₂ forms solid frost, which enables effective separation from the remaining flue gas components. This approach enables high separation efficiency and product purities exceeding 99.9%. By using sharp front model, key performance indicators were analysed to identify optimal operating conditions for capture. Different recovery strategies were also investigated to determine the most efficient pathway for melting the deposited frost into liquid CO₂. Finally, a techno-economic assessment was performed to determine the most suitable process design at large scale. Overall, the results indicate that the proposed cryogenic CO₂ capture technology can achieve highly efficient separation and shows promising economic potential, particularly when integrated with onsite cooling supply and renewable electricity sources.