An experimental study on the CO2–CH4 swap process between gaseous CO2 and CH4 hydrate in porous media

Review of natural gas hydrates as an energy resource: Prospects and challenges

“…In one study, the gas production behaviour from guest exchange process was investigated from a hydrate sample formed in pure water and unconsolidated sand [171]. The initial water saturation of the hydrate bed was 30% and a 36% CH 4 recovery from hydrate through the swapping process was achieved.…”

“…Diffusion barrier from CO 2 hydrate formation. The presence of an outer layer of mixed hydrate during the replacement process hinders mass transfer of guest species and water for further replacement [171,184]. To compute the diffusivity of CO 2 in hydrates and ice, a molecular dynamic study was conducted [185].…”

Numerical analysis of methane hydrate decomposition experiments by depressurization around freezing point in porous media

“…They are all based on the principle of shifting the thermodynamic equilibrium conditions, and gas can be extracted by one or the combinations of these methods using different kinds of well configurations [15][16][17][18][19]. Another methane production method is referred to as the CO 2 replacement, which involves the substitution of CO 2 for CH 4 in the crystal lattices [20,21]. In general, depressurization is considered to be the most practical and economic method for field hydrate decomposition due to its technical effectiveness and the fast propagating rate of the pressure wave [8].…”

Assessment of Gas Production Potential from Hydrate Reservoir in Qilian Mountain Permafrost Using Five-Spot Horizontal Well System

“…In order to realize the use of the methane gas trapped in gas hydrates as a kind of energy resource, people have proposed various kinds of production techniques for gas extraction from hydrate deposits, such as depressurization [9][10][11][12], thermal stimulation [13][14][15], inhibitor injection [16,17], and CO2 replacement [18,19]. In general, depressurization is considered to be the most practical and economic method for field-scale hydrate decomposition due to its technical effectiveness and the fast propagating rate of the pressure wave [12].…”