Enhanced gas recovery by CO2 sequestration in marine shale: a molecular view based on realistic kerogen model

Influence of Pore Structure on Shale Gas Recovery with CO2 Sequestration: Insight Into Molecular Mechanisms

“…Therefore, the relative density difference between the bulk phase and the adsorbed phase becomes smaller as pressure increases. These tendencies are consistent with experiments , and molecular simulations. ,, The excess adsorption capacity of CH 4 and CO 2 is in the order of cylinder-shaped, bottleneck, wedge-shaped, and slit-shaped. The corresponding pressures at the peaks are similar for different pores structures.…”

“…These tendencies are consistent with experiments 61,62 and molecular simulations. 5,31,47 The excess adsorption capacity of CH 4 and CO 2 is in the order of cylinder-shaped, bottleneck, wedge-shaped, and slit-shaped.…”

“…42 Although some molecular dynamicsbased shale kerogen pores were constructed to investigate the adsorption of methane in shale, Huang et al considered the factors of pressures, temperatures, geological depths, kerogen maturity, moisture content, and kerogen organic type on adsorption of CH 4 and CO 2 using GCMC and MC methods. 5,43,31 Zhou 44 and Collell 45 et al figured out the effect of pore size on adsorption. Perez et al investigated the spatial distribution of reservoir fluids in mature kerogen using molecular simulations.…”

“…Shale gas adsorption capacity is determined by a combination effect of many factors; previous studies mainly focus on the influence factors such as total organic carbon (TOC) content, moisture content, , thermal maturity, , shale composition, pore size, porosity, pressure, and temperature, , but few studies shed light on the effect of pore structure on shale gas adsorption capacity for the reason that it is difficult to exactly investigate the pore structure effect on shale gas adsorption considering the heterogeneous and complex nature of shale. Some scholars have done similar research of the pore structures effect on the adsorption of methane based on graphite slit-pores and carbon nanotubes as organic matrix models .…”

“…Molecular simulation is the common effective method to study shale gas adsorption behavior because of the characteristics of shale pores, whose average pore size is 3–5 nm. − Based on realistic kerogen model, Zhao et al studied the effects of water content on methane adsorption capacity using the molecular dynamics (MD) and Monte Carlo (MC) simulation methods . Although some molecular dynamics-based shale kerogen pores were constructed to investigate the adsorption of methane in shale, Huang et al considered the factors of pressures, temperatures, geological depths, kerogen maturity, moisture content, and kerogen organic type on adsorption of CH 4 and CO 2 using GCMC and MC methods. ,, Zhou and Collell et al figured out the effect of pore size on adsorption. Perez et al investigated the spatial distribution of reservoir fluids in mature kerogen using molecular simulations .…”