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Sun S, Gao M, Liang S, Liu Y. Hydrocarbon Transportation in Heterogeneous Shale Pores by Molecular Dynamic Simulation. Molecules 2024; 29:1763. [PMID: 38675583 PMCID: PMC11052224 DOI: 10.3390/molecules29081763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/24/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
Shale oil in China is widely distributed and has enormous resource potential. The pores of shale are at the nanoscale, and traditional research methods encounter difficulty in accurately describing the fluid flow mechanism, which has become a bottleneck restricting the industrial development of shale oil in China. To clarify the distribution and migration laws of fluid microstructure in shale nanopores, we constructed a heterogeneous inorganic composite shale model and explored the fluid behavior in different regions of heterogeneous surfaces. The results revealed the adsorption capacity for alkanes in the quartz region was stronger than that in the illite region. When the aperture was small, solid-liquid interactions dominated; as the aperture increased, the bulk fluid achieved a more uniform and higher flow rate. Under conditions of small aperture/low temperature/low pressure gradient, the quartz region maintained a negative slip boundary. Illite was more hydrophilic than quartz; when the water content was low, water molecules formed a "liquid film" on the illite surface, and the oil flux percentages in the illite and quartz regions were 87% and 99%, respectively. At 50% water content, the adsorbed water in the illite region reached saturation, the quartz region remained unsaturated, and the difference in the oil flux percentage of the two regions decreased. At 70% water content, the adsorbed water in the two regions reached a fully saturated state, and a layered structure of "water-two-phase region-water" was formed in the heterogeneous nanopore. This study is of great significance for understanding the occurrence characteristics and flow mechanism of shale oil within inorganic nanopores.
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Affiliation(s)
- Shuo Sun
- Department of Petroleum Engineering, Northeast Petroleum University, Daqing 163318, China
- Key Laboratory of Enhanced Oil Recovery, Northeast Petroleum University, Ministry of Education, Daqing 163318, China
| | - Mingyu Gao
- The No.2 Oil Production Plant of Northwest Petroleum Bureau, Kuche 842000, China
| | - Shuang Liang
- Department of Petroleum Engineering, Northeast Petroleum University, Daqing 163318, China
- Key Laboratory of Enhanced Oil Recovery, Northeast Petroleum University, Ministry of Education, Daqing 163318, China
| | - Yikun Liu
- Department of Petroleum Engineering, Northeast Petroleum University, Daqing 163318, China
- Key Laboratory of Enhanced Oil Recovery, Northeast Petroleum University, Ministry of Education, Daqing 163318, China
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Dastjerdi AM, Kharrat R, Niasar V, Ott H. Salinity-Driven Structural and Viscosity Modulation of Confined Polar Oil Phases by Carbonated Brine Films: Novel Insights from Molecular Dynamics. J Phys Chem B 2024; 128:1780-1795. [PMID: 38334946 DOI: 10.1021/acs.jpcb.3c07300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
The structural and dynamic properties of fluids under confinement in a porous medium differ from their bulk properties. This study delves into the surface structuring and hydrodynamic characteristics of oil/thin film carbonated brine two-phase within a calcite channel upon salinity variation. To this end, both equilibrium and non-equilibrium molecular dynamics simulations are utilized to unveil the effect of the carboxylic acid component (benzoic acid) in a simple model oil (decane) confined between two thin films of carbonated brine on the oil-brine-calcite characteristics. The salinity effect was scrutinized under four saline carbonated waters, deionized carbonated water (DCW), carbonated low-salinity brine (CLSB, 30,000 ppm), carbonated seawater (CSW, 60,000 ppm), and carbonated high-salinity brine (CHSB, 180,000 ppm). An electrical double layer (EDL) is observed at varying salinities, comprising a Stern-like positive layer (formed by Na+ ions) followed by a negative one (formed by Cl- ions primarily residing on top of the adsorbed sodium cations). By lowering the salinity, the Na+ ions cover the interface regions (brine-calcite and brine-oil), depleting within the brine bulk region. The lowest positive surface charge on the rock surface was found in salinity corresponding to seawater. Two distinct Na+ peaks at the oleic phase interface have been observed in the carbonated high-salinity brine system, enhancing the adsorption of polar molecules at the thin brine film interfaces. There is a pronounced EDL formation at the oleic phase interface in the case of CSW, resulting in a strong interface region containing ions and functional fractions. Likewise, the oil region confined by CSW exhibited the lowest apparent viscosity, attributed to the optimized salinity distribution and inclination of benzoic acid fractions uniformly at the brine-oil interface, acting as a slippery surface. Moreover, the results reveal that the presence of polar fractions could increase the oil phase's apparent viscosity, and introducing ions to this system reduces the polar molecules' destructive effect on the apparent viscosity of the oil region. Therefore, the fluidity of confined systems is modulated by both composition of the brine and oil phases.
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Affiliation(s)
| | - Riyaz Kharrat
- Department Petroleum Engineering, Montanuniversität Leoben, Leoben 8700, Austria
| | - Vahid Niasar
- Department of Chemical Engineering, The University of Manchester,, Manchester M139PL, U.K
| | - Holger Ott
- Department Petroleum Engineering, Montanuniversität Leoben, Leoben 8700, Austria
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Duan L, Zhang M, Nan Y, Jin Z. Effects of Interfacial Molecular Structures on Pressure-Driven Brine Flow in Silica Mesopores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:13019-13027. [PMID: 37669184 DOI: 10.1021/acs.langmuir.3c01200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
In this work, we conduct molecular dynamics simulations to investigate pressure-driven brine flow in silica mesopores under typical reservoir conditions (323 K and 20 MPa). While surface counterions accumulate strongly in the vicinity of fully deprotonated silica surfaces, water forms multilayer structures due to hydrogen bonding, counterion hydration, and excluded-volume effect. Brine flow behaviors exhibit adsorption, transition, and bulk-like regions in fully deprotonated silica mesopores, while the transition region is negligible in fully protonated ones. In the adsorption region, strong surface hydrogen bonding and a high degree of counterion hydration collectively hinder water mobility. Even without surface hydrogen bonding, persistent ion hydration impedes water flow, leading to the transition region in fully deprotonated silica mesopores and higher viscosity of brine (with 10 wt % NaCl) in the bulk region. This work elucidates the collective effects of surface chemistry and interfacial water structures on brine flow behaviors in silica mesopores from molecular perspectives.
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Affiliation(s)
- Lian Duan
- School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Mingshan Zhang
- Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines, School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China
| | - Yiling Nan
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, United States
| | - Zhehui Jin
- School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
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Zhao Z, Jin Y, Zhou R, Sun C, Huang X. Unexpected Behavior in Thermal Conductivity of Confined Monolayer Water. J Phys Chem B 2023; 127:4090-4098. [PMID: 37105181 DOI: 10.1021/acs.jpcb.2c07506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Monolayer water can be formed under extreme confinement and will present distinctive thermodynamic properties compared with bulk water. In this work, we perform molecular dynamics simulations to study the thermal conductivity of monolayer water confined in graphene channels, finding an unexpected way of thermal conductivity of monolayer water dependent on its number density, which has a close correlation with the structure of water. The monolayer water is in an amorphous state, and its thermal conductivity increases linearly with the area density when the water density is low at first. Then, the thermal conductivity increases as the number density of water rises, which is attributed to the formation of a crystal structure and the reduction of crystal defects as the number of water molecules increases. After reaching the zenith, the thermal conductivity decreases rapidly owing to the formation of a wrinkle structure of monolayer water with excessive water molecules, which weakens the phonon dispersion. Moreover, we further investigate the remarkable effects of the channel height on both the structure and thermal conductivity of monolayer water. In summary, this study demonstrates the close connection between the thermal conductivity of monolayer water and its structure, contributing to not only expanding the understanding of the thermodynamic property of nanoconfined water but also benefiting the engineering applications for nanofluidics.
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Affiliation(s)
- Zhixiang Zhao
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
| | - Yonghui Jin
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
| | - Runfeng Zhou
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Shaanxi 710049, China
| | - Chengzhen Sun
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Shaanxi 710049, China
| | - Xiang Huang
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
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Sun S, Liang S, Liu Y, Liu D, Gao M, Tian Y, Wang J. A Review on Shale Oil and Gas Characteristics and Molecular Dynamics Simulation for the Fluid Behavior in Shale Pore. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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6
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Carbon dioxide-enhanced metal release from kerogen. Sci Rep 2022; 12:15196. [PMID: 36071133 PMCID: PMC9452497 DOI: 10.1038/s41598-022-19564-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/31/2022] [Indexed: 11/19/2022] Open
Abstract
Heavy metals released from kerogen to produced water during oil/gas extraction have caused major enviromental concerns. To curtail water usage and production in an operation and to use the same process for carbon sequestration, supercritical CO2 (scCO2) has been suggested as a fracking fluid or an oil/gas recovery agent. It has been shown previously that injection of scCO2 into a reservoir may cause several chemical and physical changes to the reservoir properties including pore surface wettability, gas sorption capacity, and transport properties. Using molecular dynamics simulations, we here demonstrate that injection of scCO2 might lead to desorption of physically adsorbed metals from kerogen structures. This process on one hand may impact the quality of produced water. On the other hand, it may enhance metal recovery if this process is used for in-situ extraction of critical metals from shale or other organic carbon-rich formations such as coal.
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Molecular simulation study of oil-water two-phase fluid transport in shale inorganic nanopores. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2021.116948] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Ho TA, Wang Y. Molecular Origin of Wettability Alteration of Subsurface Porous Media upon Gas Pressure Variations. ACS APPLIED MATERIALS & INTERFACES 2021; 13:41330-41338. [PMID: 34410713 DOI: 10.1021/acsami.1c11540] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Upon extraction/injection of a large quantity of gas from/into a subsurface system in shale gas production or carbon sequestration, the gas pressure varies remarkably, which may significantly change the wettability of porous media involved. Mechanistic understanding of such changes is critical for designing and optimizing a related subsurface engineering process. Using molecular dynamics simulations, we have calculated the contact angle of a water droplet on various solid surfaces (kerogen, pyrophyllite, calcite, gibbsite, and montmorillonite) as a function of CO2 or CH4 gas pressure up to 200 atm at a temperature of 300 K. The calculation reveals a complex behavior of surface wettability alteration by gas pressure variation depending on surface chemistry and structure, and molecular interactions of fluid molecules with surfaces. As the CO2 gas pressure increases, a partially hydrophilic kerogen surface becomes highly hydrophobic, while a calcite surface becomes more hydrophilic. Considering kerogen and calcite being the major components of a shale formation, we postulate that the wettability alteration of a solid surface induced by a gas pressure change may play an important role in fluid flows in shale gas production and geological carbon sequestration.
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Affiliation(s)
- Tuan A Ho
- Geochemistry Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Yifeng Wang
- Nuclear Waste Disposal Research and Analysis Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
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Fang T, Li S, Zhang Y, Su Y, Yan Y, Zhang J. How the oil recovery in deep oil reservoirs is affected by injected gas types: A molecular dynamics simulation study. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2020.116286] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Zhao G, Yao Y, Adenutsi CD, Feng X, Wang L, Wu W. Transport Behavior of Oil in Mixed Wettability Shale Nanopores. ACS OMEGA 2020; 5:31831-31844. [PMID: 33344837 PMCID: PMC7745427 DOI: 10.1021/acsomega.0c04678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/30/2020] [Indexed: 06/12/2023]
Abstract
Shale oil reserves play an important role in the oil & gas industry. The investigation of oil transport behavior in shale nanopores is crucial in the successful exploitation of shale oil reservoirs. However, the transport mechanisms of oil in shale nanopores are still not understood. In this paper, a model for oil transport through a single nanopore was established by considering mixed wettability, surface roughness, varying viscosity, and the effects triggered by adsorbed organic matter. The organic surface ratio of a single nanopore was used to quantify mixed wettability, while the effects of adsorbed organic matter were estimated by the surface coverage and the adsorption thickness. The entire mathematical model was simplified into several equations to discuss the contributions of each mechanism. The results showed that to accurately predict the oil transport properties in mixed wettability shale nanopores, it is necessary to consider varying viscosity, wettability alteration, and the oil molecule structure. Adsorbed organic matter led to increase in oil flow capacity by altering the surface wettability. However, the oil flow capacity was greatly reduced when varying viscosity was considered. Additionally, the contributions of each mechanism varied with the pore type. Furthermore, increasing surface roughness significantly reduced the oil flow capacity in both organic and inorganic nanopores. This work provides a better understanding of oil transport behavior in mixed-wettability shale nanopores and a quantitative framework for future research.
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Affiliation(s)
- Guoxiang Zhao
- College
of Petroleum Engineering, China University
of Petroleum, Beijing 102249, China
| | - Yuedong Yao
- College
of Petroleum Engineering, China University
of Petroleum, Beijing 102249, China
| | - Caspar Daniel Adenutsi
- Core
and Rock Properties Laboratory, Department of Petroleum Engineering,
Faculty of Civil and Geo-Engineering, Kwame
Nkrumah University of Science and Technology, Kumasi AK, Ghana
| | - Xiaolong Feng
- No.1
Oil Production Plant, Changqing Oilfield, PetroChina, Yan’an 716000, China
| | - Lian Wang
- College
of Petroleum Engineering, China University
of Petroleum, Beijing 102249, China
| | - Wenwei Wu
- Ningbo
Fengcheng Advanced Energy Materials Research Institute, Ningbo 315000, China
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11
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Lei Z, Lai L, Sun Z, Wu K. Comprehensive Model for Oil Transport Behavior in Nanopores: Interactions between Oil and Pore Surface. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhengdong Lei
- Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China
| | - Lingbin Lai
- Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China
| | - Zheng Sun
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, China
| | - Keliu Wu
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, P. R. China
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Fan D, Ettehadtavakkol A, Wang W. Apparent Liquid Permeability in Mixed-Wet Shale Permeable Media. Transp Porous Media 2020. [DOI: 10.1007/s11242-020-01462-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractApparent liquid permeability (ALP) in ultra-confined permeable media is primarily governed by the pore confinement and fluid–rock interactions. A new ALP model is required to predict the interactive effect of the above two on the flow in mixed-wet, heterogeneous nanoporous media. This study derives an ALP model and integrates the compiled results from molecular dynamics (MD) simulations, scanning electron microscopy, atomic force microscopy, and mercury injection capillary pressure. The ALP model assumes viscous forces, capillary forces, and liquid slippage in tortuous, rough pore throats. Predictions of the slippage of water and octane are validated against MD data reported in the literature. In up-scaling the proposed liquid transport model to the representative-elementary-volume scale, we integrate the geological fractals of the shale rock samples including their pore size distribution, pore throat tortuosity, and pore-surface roughness. Sensitivity results for the ALP indicate that when the pore size is below 100 nm pore confinement allows oil to slip in both hydrophobic and hydrophilic pores, yet it also restricts the ALP due to the restricted intrinsic permeability. The ALP reduces to the well-established Carman–Kozeny equation for no-slip viscous flow in a bundle of capillaries, which reveals a distinguishable liquid flow behavior in shales versus conventional rocks. Compared to the Klinkenberg equation, the proposed ALP model reveals an important insight into the similarities and differences between liquid versus gas flow in shales.
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13
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Rezlerová E, Brennan JK, Lísal M. Methane and carbon dioxide in
dual‐porosity
organic matter: Molecular simulations of adsorption and diffusion. AIChE J 2020. [DOI: 10.1002/aic.16655] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Eliška Rezlerová
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences Institute of Chemical Process Fundamentals Prague Czech Republic
- Department of Physics, Faculty of Science J. E. Purkinje University Ústí n. Lab Czech Republic
| | - John K. Brennan
- Weapons and Materials Research Directorate U.S. Army Combat Capabilities Development Command Army Research Laboratory Aberdeen Proving Ground Maryland USA
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences Institute of Chemical Process Fundamentals Prague Czech Republic
- Department of Physics, Faculty of Science J. E. Purkinje University Ústí n. Lab Czech Republic
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Zhan S, Su Y, Jin Z, Wang W, Cai M, Li L, Hao Y. Molecular insight into the boundary conditions of water flow in clay nanopores. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113292] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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16
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Kang C, Kim D. Nanoconfinement-mediated cancer theranostics. Arch Pharm Res 2020; 43:110-117. [PMID: 31989481 DOI: 10.1007/s12272-020-01217-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 01/20/2020] [Indexed: 10/25/2022]
Abstract
Despite various therapeutic or diagnostic developments, cancer is still one of the most lethal diseases due to insufficiently adequate treatments and the delay of the early stage of disease detection. An image-guided drug delivery system (IGDDS), as a real-time noninvasive imaging assessment of therapeutic response, has the strong potential to improve the diagnosis and treatment of cancer because its imaging property offers the quantification of nanomedicine at the intended disease sites, the possible assurance of adequate treatment and elimination of undesirable delay of early-stage diagnosis due to low resolution. One of potential modality that overcomes these challenges could be the nanoconfinement of gold (Au) nanoparticles within other nanoparticles called "Particle-in-Particle (PIP)", which is a strong candidate of cancer treatment because of its "theranostic (therapy + diagnostics)" advantages including imaging (e.g., CT) and therapeutic hyperthermia application. In this review, we will elaborate on the current application of theranostic by nanoconfinement. Then, we will narrow down the gold nanoparticle-mediated theranostic application and its nanoconfinement advantages. Finally, the future direction for maximum nanoconfinement mediated cancer therapy will be included.
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Affiliation(s)
- Changsun Kang
- Department of Pharmaceutical Sciences, Rangel College of Pharmacy, Texas A&M University, College Station, USA
| | - Dongin Kim
- Department of Pharmaceutical Sciences, Rangel College of Pharmacy, Texas A&M University, College Station, USA.
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Zhou W, Zhang Z, Wang H, Yang X. Molecular Investigation of CO 2/CH 4 Competitive Adsorption and Confinement in Realistic Shale Kerogen. NANOMATERIALS (BASEL, SWITZERLAND) 2019; 9:E1646. [PMID: 31756918 PMCID: PMC6956192 DOI: 10.3390/nano9121646] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/12/2019] [Accepted: 11/17/2019] [Indexed: 12/23/2022]
Abstract
The adsorption behavior and the mechanism of a CO2/CH4 mixture in shale organic matter play significant roles to predict the carbon dioxide sequestration with enhanced gas recovery (CS-EGR) in shale reservoirs. In the present work, the adsorption performance and the mechanism of a CO2/CH4 binary mixture in realistic shale kerogen were explored by employing grand canonical Monte Carlo (GCMC) and molecular dynamics (MD) simulations. Specifically, the effects of shale organic type and maturity, temperature, pressure, and moisture content on pure CH4 and the competitive adsorption performance of a CO2/CH4 mixture were investigated. It was found that pressure and temperature have a significant influence on both the adsorption capacity and the selectivity of CO2/CH4. The simulated results also show that the adsorption capacities of CO2/CH4 increase with the maturity level of kerogen. Type II-D kerogen exhibits an obvious superiority in the adsorption capacity of CH4 and CO2 compared with other type II kerogen. In addition, the adsorption capacities of CO2 and CH4 are significantly suppressed in moist kerogen due to the strong adsorption strength of H2O molecules on the kerogen surface. Furthermore, to characterize realistic kerogen pore structure, a slit-like kerogen nanopore was constructed. It was observed that the kerogen nanopore plays an important role in determining the potential of CO2 subsurface sequestration in shale reservoirs. With the increase in nanopore size, a transition of the dominated gas adsorption mechanism from micropore filling to monolayer adsorption on the surface due to confinement effects was found. The results obtained in this study could be helpful to estimate original gas-in-place and evaluate carbon dioxide sequestration capacity in a shale matrix.
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Affiliation(s)
- Wenning Zhou
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; (Z.Z.); (H.W.); (X.Y.)
- Beijing Key Laboratory of Energy Saving and Emission Reduction for Metallurgical Industry, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhe Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; (Z.Z.); (H.W.); (X.Y.)
| | - Haobo Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; (Z.Z.); (H.W.); (X.Y.)
| | - Xu Yang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; (Z.Z.); (H.W.); (X.Y.)
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