Unconventional natural gas extraction has undergone rapid progress in recent years as an emerging energy source, and the amount of methane gas stored in gas hydrates is estimated to be larger than that of all other natural gas resources combined. In the process of finding suitable hydrate reservoirs for possible exploitation and other applications, it is vital to understand the effect of reservoir conditions on the formation kinetics of methane gas hydrates. The aim of this study is to investigate hydrate formation characteristics in a porous medium under different confining conditions, focusing on the effect of confining pressure on hydrate nucleation, growth, and saturation. A series of experiments was performed to simulate in-situ hydrate reservoir conditions in a custom-designed reactor to synthesise methane hydrates in a porous quartz sand medium under different confining and formation pressures. Temporal changes in gas pressure and temperature were incorporated to quantify the co
Extraction of methane from natural gas hydrates whilst storing CO2 via gas replacement is a promising approach for reducing anthropogenic CO2 emissions during energy generation. In this study, molecular dynamic simulations were performed to identify the influence of temperature, pressure, and the initial CO2 concentration of sweep gas on the gas replacement characteristics. Simulations were performed under selected pressure and temperature conditions using five different initial CO2 concentrations. The simulation results clearly portray the replacement phenomena where methane molecules are released into the free gas layer while CO2 get enclathrated in hydrate structure. During gas replacement, minor structural changes in hydrate structure can also be observed, but they are quite insignificant as demonstrated through the alterations in Tetrahedrality order parameter. The variations of the number densities of gas and water molecules during gas replacement were used to quantify the methan