Research on micro mechanism and influence of hydrate-based methane-carbon dioxide replacement for realizing simultaneous clean energy exploitation and carbon emission reduction

New energy development and carbon emission reduction are two important issues of sustainable development for human beings. Hydrate-based methane - carbon dioxide (CH4-CO2) replacement is the promising technology for it can realize CH4 production from natural gas hydrate (NGH) and CO2 capture and sequestration (CCS) in the strata simultaneously and stably. This work reported the micro mechanism and the influence of the hydrate-based CH4-CO2 replacement by differential scanning calorimetry (DSC) measurements and in situ Raman spectroscopy measurements. It was found the replacement is affected by the potential energy of destruction (Eped) and the binding energy (Eb). The replacement happens only when the Eped is larger than the Eb. The concentration of CO2 around the hydrate is the controlling influence on the replacement. The higher the concentration of CO2, the greater the Eped, and the higher CH4 production efficiency.