Carbon sequestration in overlying methane hydrate layers via hydrate technology: Feasibility and synergistic benefits

Excessive carbon dioxide emissions pose a global environmental issue, and carbon sequestration technology offers a solution. This study based on independently developed simulator proposes a novel approach for carbon dioxide sequestration in the overlying layers of methane hydrate reservoirs using carbon dioxide hydrate technology. The feasibility and risks of this method are evaluated over a time scale of 100,000 years. Results show that carbon dioxide migrates upwards after injection, forming highly saturated hydrate shells at the migration front. Within these carbon dioxide hydrate shells, a portion of the carbon dioxide is sequestered in liquid and dissolved forms; however, over tens of thousands of years, 20 % of the CO₂ will dissolve, while less than 1 % will escape. The study highlights the synergy between methane hydrate extraction and carbon sequestration, as the cold seawater down draw effect from extraction enhances sequestration efficiency and safety. Given the widespread distribution of methane hydrate reservoirs globally, this research provides new insights into carbon sequestration technology.