Molecular characterization of carbon dioxide, methane, and water adsorption in micropore space of kerogen matrix

FUEL

卷:283

Article

Chong, Leebyn^1,2  Sanguinito, Sean^1,3  Goodman, Angela L.¹  Myshakin, Evgeniy M.^1,3 

[1] Natl Energy Technol Lab, POB 10940, Pittsburgh, PA 15236 USA

[2] Oak Ridge Inst Sci & Educ, 100 ORAU Way, Oak Ridge, TN 37830 USA

[3] Leidos Res Support Team, Pittsburgh, PA 15236 USA

关键词: Molecular simulations;    Kerogen;    Shales;    Adsorption in porous media;    Carbon dioxide storage;    Enhanced gas production;   

DOI  :  10.1016/j.fuel.2020.119254

来源: Elsevier

【 摘 要 】

Carbon dioxide and methane interaction with organic matter mostly represented by kerogen heavily impacts carbon storage and enhanced gas recovery in shales. Kerogen pores are dominated by micropore network connecting mesopores and understanding adsorption in kerogen is a key element for estimation of shale capacity to retain and release fluids. In this work, molecular dynamics and Monte Carlo simulations were engaged to study adsorption of carbon dioxide, methane, and water in immature type II-A kerogen. Fluid adsorption induces volumetric swelling and pore space expansion with water imposing the largest impact compared to carbon dioxide and methane. The adsorption isotherms show that water demonstrates the highest uptake (up to 6.2 mmol/g) which is attributed to strong water-kerogen energy interaction and the tendency to form large water clusters. On the other hand, methane and carbon dioxide show similar adsorption (up to 1.5 mmol/g) in the micropore space of kerogen. The analysis of cluster size distributions implies a large extent of a disconnectivity in micro pores with adsorbed carbon dixoide and methane, while micropores demonstrate continuity with adsorbed water.

【 授权许可】

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