Dr. Vaibhav Bahadur, an associate professor in the Walker Department of Mechanical Engineering and an affiliate of the Texas Materials Institute, was part of a team of researchers who have published a review of hydrate-based gas separation (HBGS), an alternative method promising to capture CO2 from industrial gases in an effort to reduce greenhouse gas emissions. They used results from more than 50 experimental studies and compared the cost of HBGS to the established technology of monoethanolamine (MEA) absorption.
Overall, the team found that HBGS can effectively separate CO2 from industrial gas and that certain chemical additives allow the hydrates to form unless less demanding temperature and pressure conditions. They also found that the cost range for the technology was approximately $25 to $145 per metric ton of CO2, compared to the MEA-based technology rates of $40 to $120 per metric ton. Because the greatest costs and energy use were due to compressing the gas and keeping it cold, the environmental savings depend on how the electricity for these procedures is produced.
While there were promising results, some aspects need to be studied before HBGS can be widely deployed, including the inefficiencies of separating the hydrates from saltwater and a life-cycle assessment. Only after these possible barriers are investigated can we really determine if HGBS offers a meaningful environmental advantage over existing technologies like MEA-based capture.
Read the full article, "Review of clathrate hydrate-based CO2 capture: Benchmarking performance, economics, and life cycle considerations," at the Journal of Environmental Chemical Engineering.
