Pore-scale thermo-hydro-chemical coupling numerical simulation for in-situ thermal upgrading of low-to-medium maturity shale oil

Yubao Gao, Yingfeng Peng, Weiyao Zhu, Wengang Bu, Fuyong Wang and Debin Kong

Energy, 2025, vol. 330, issue C

Abstract: In-situ thermal upgrading (ITU) is key to the efficient exploitation of low-to-medium maturity shale oil (LMSO) resources. It is a complex process involving chemical reaction, heat transfer, and fluid flow. To thoroughly investigate the pyrolysis kinetics of LMSO at the pore-scale, this study proposes a coupled thermo-hydro-chemical numerical simulation approach. A novel multi-component characteristic parameter model is developed to quantify the dynamic evolution of fluid properties during multi-stage kerogen pyrolysis. Comparative analysis reveals that the original static parameter model underestimates the production of methane, other gases, and light oil, while overestimating that of heavy oil. The pyrolysis process induces a remarkable transformation in the reservoir properties, with the porosity and permeability increasing from 0.013 and 0.0006 mD to 0.28 and 6.4 mD, respectively, which significantly enhances the flow capacity. Sensitivity analysis reveals that the kerogen content is positively correlated with the total yield of cracking products. When kerogen content increases by 28.6 %, the total yields of heavy oil, light oil, other gases, and methane increase by 50.4 %, 20.8 %, 17.8 %, and 27.3 %, respectively. Furthermore, when specific heat capacity rises from 1380 to 1980 J/(kg·K), the kerogen pyrolysis time increases by a factor of 1.4. Conversely, increasing heating rate by a factor of 1.9 reduces the cracking time by 13.6 min. The maximum yields of heavy oil, light oil, and other gases occurred at distinct thermal thresholds of 400, 500, and 570 °C, respectively. This study provides a theoretical basis for optimizing ITU process parameters and improving the energy efficiency of LMSO.

Keywords: In-situ thermal upgrading; Low-to-medium maturity; Shale oil; Thermo-hydro-chemical coupling; Production performance; Sensitivity analysis (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225026131
Full text for ScienceDirect subscribers only

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:eee:energy:v:330:y:2025:i:c:s0360544225026131

DOI: 10.1016/j.energy.2025.136971

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().