Investigating CO2 Replacement for the Exploitation of Natural Gas Hydrates: Characteristics and Control Parameters

In response to escalating global energy demand and climate change mitigation needs, natural gas hydrates (NGHs) are gaining prominence as a clean energy source. The CO2 replacement method is an innovative NGH extraction technique that reduces reservoir risks and enables CO2 sequestration. However, our understanding of the dynamics and control parameters in the hydrate replacement process is limited. This study pioneers a kinetic analysis and conceptual model for a CO2-driven hydrate replacement, dividing the process into three spatial realms and sequential stages. We identify the optimal injection temperature range for standard NGH reservoirs and highlight the interplay between the gas injection rate and bottom-hole pressure on CH4 yield. Our findings offer insights on how to optimize production efficiency and gas separation, advancing CO2 replacement technology for NGHs.