Abstract

Pore structure characterization and its effect on methane adsorption on shale kerogen are crucial to understanding the fundamental mechanisms of gas storage, transport, and reserves evaluation. In this study, we use 3D scanning confocal microscopy, scanning electron microscopy (SEM), X-ray nano-computed tomography (nano-CT), and low-pressure N2 adsorption analysis to analyze the pore structures of the shale. Additionally, the adsorption behavior of methane on shales with different pore structures is investigated by molecular simulations. The results show that the SEM image of the shale sample obviously displays four different pore shapes, including slit pore, square pore, triangle pore, and circle pore. The average coordination number is 4.21 and the distribution of coordination numbers demonstrates that pores in the shale have high connectivity. Compared with the adsorption capacity of methane on triangle pores, the adsorption capacity on slit pore, square pore, and circle pore are reduced by 9.86%, 8.55%, and 6.12%, respectively. With increasing pressure, these acute wedges fill in a manner different from the right or obtuse angles in the other pores. This study offers a quantitative understanding of the effect of pore structure on methane adsorption in the shale and provides better insight into the evaluation of gas storage in geologic shale reservoirs.

Details

Title
Pore structure characterization and its effect on methane adsorption in shale kerogen
Author
Tian-Yu, Wang 1 ; Tian Shou-Ceng 1 ; Qing-Ling, Liu 2 ; Li, Gen-Sheng 3 ; Mao, Sheng 1 ; Wen-Xi, Ren 4 ; Pan-Pan, Zhang 1 

 China University of Petroleum (Beijing), State Key Laboratory of Petroleum Resources and Prospecting, Beijing, China (GRID:grid.411519.9) (ISNI:0000 0004 0644 5174); Harvard SEAS-CUPB Joint Laboratory on Petroleum Science, Cambridge, USA (GRID:grid.411519.9) 
 China National Oil and Gas Exploration and Development Company Ltd, Beijing, China (GRID:grid.411519.9) 
 China University of Petroleum (Beijing), State Key Laboratory of Petroleum Resources and Prospecting, Beijing, China (GRID:grid.411519.9) (ISNI:0000 0004 0644 5174) 
 China University of Petroleum (Beijing), State Key Laboratory of Petroleum Resources and Prospecting, Beijing, China (GRID:grid.411519.9) (ISNI:0000 0004 0644 5174); Southwest Petroleum University, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu, China (GRID:grid.437806.e) (ISNI:0000 0004 0644 5828) 
Pages
565-578
Publication year
2021
Publication date
Apr 2021
Publisher
KeAi Publishing Communications Ltd
ISSN
16725107
e-ISSN
19958226
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2510636087
Copyright
© The Author(s) 2020. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.