Direct Visualization of Nanoscale Salt Precipitation and Dissolution Dynamics during CO 2 Injection

Xinling Hu, Jian Wang, Liang Zhang, Hongli Xiong, Zengding Wang, Huazheng Duan, Jun Yao, Hai Sun, Lei Zhang, Wenhui Song and Junjie Zhong ()
Additional contact information
Xinling Hu: Exploration and Development Research Institute Sinopec Jianghan Oilfield Company, Wuhan 430223, China
Jian Wang: Exploration and Development Research Institute Sinopec Jianghan Oilfield Company, Wuhan 430223, China
Liang Zhang: Exploration and Development Research Institute Sinopec Jianghan Oilfield Company, Wuhan 430223, China
Hongli Xiong: Exploration and Development Research Institute Sinopec Jianghan Oilfield Company, Wuhan 430223, China
Zengding Wang: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Huazheng Duan: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Jun Yao: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Hai Sun: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Lei Zhang: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Wenhui Song: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
Junjie Zhong: Research Center of Multiphase Flow in Porous Media, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China

Energies, 2022, vol. 15, issue 24, 1-14

Abstract: CO 2 injection to enhance shale oil recovery provides a win-win solution to meet the global fuel shortage and realize ultimate carbon neutrality. When shale reservoirs contain high salinity water, CO 2 injection can result in salt precipitation to block the nanometer pores in the shale, causing undesirable formation damage. Understanding salt precipitation and dissolution dynamics at the nanoscale are fundamental to solving this practical challenge. In this work, we developed a shale micromodel to characterize salt precipitation and dissolution based on nanofluidic technology. By directly distinguishing different phases from 50 nm to 5 ?m, we identified the salt precipitation sites and precipitation dynamics during the CO 2 injection. For the salt precipitation in the nanometer network, we identified two precipitation stages. The ratio of the precipitation rates for the two stages is ~7.9 times that measured in microporous media, because of the slow water evaporation at the nanoscale. For the salt precipitation in the interconnected micrometer pores, we found that the CO 2 displacement front serves as the salt particle accumulating site. The accumulated salt particles will in turn impede the CO 2 flow. In addition, we also studied the salt dissolution process in the shale micromodel during water injection and found the classical dissolution theory overestimates the dissolution rate by approximately twofold. This work provides valuable pore-scale experimental insight into the salt precipitation and dissolution dynamics involved in shale formation, with the aim to promote the application of CO 2 injection for shale oil recovery.

Keywords: CCUS; CO 2 injection; shale oil; microfluidics; salt precipitation (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2022
References: View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/1996-1073/15/24/9567/pdf (application/pdf)
https://www.mdpi.com/1996-1073/15/24/9567/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:15:y:2022:i:24:p:9567-:d:1005842

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().