CO2 Gas Hydrate for Carbon Capture and Storage Applications – Part 1

Gas hydrates are solid crystalline compounds formed by water and gas molecules through molecular interactions, typically at low temperatures and high pressures. While gas hydrates are generally known as flow assurance challenges for the oil and gas industries (e.g., pipeline blockages), numerous studies have shown the potential application of gas hydrate in carbon capture and storage (CCS). Due to the more thermodynamic stability of CO2 hydrate compared to other industrial emission gas components like nitrogen, CO2 hydrates have emerged as a viable mechanism for CO2 capture. Moreover, a large volume of CO2 can be stored securely in the stable structure of gas hydrates, providing an additional benefit for CO2 storage in geological formations. Thus, gas hydrates can be suggested as a technology for mitigating CO2 emissions. Notwithstanding the CO2 hydrate advantages in CCS, they may also present some challenges, particularly in terms of flow assurance. For example, CO2 hydrate formation during CO2 transportation can cause a serious pipeline blockage. Therefore, the fundamental understanding of gas hydrates is crucial for CCS. In the first part of this review, the principle on gas hydrates (especially CO2 hydrates) and CO2 hydrate-based carbon capture are discussed.