Pore-scale Competitive Migration and Selective Regulation of Multi-component Hydrocarbons in Continental Shale Oil: A Phase-field Modeling Study

Authors

  • Fuqiang Xu Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China https://orcid.org/0000-0002-5898-6672
  • Zhigang Liu Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China
  • Can Ji Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China
  • Rubing Han Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China https://orcid.org/0009-0002-4822-5818
  • Yan Liu Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China https://orcid.org/0009-0006-6261-0703
  • Aimin Chen Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, Shandong, China https://orcid.org/0009-0009-8556-4932

DOI:

https://doi.org/10.15377/2409-787X.2026.13.3

Keywords:

Phase-field model, Continental shale oil, Competitive seepage, Pore-scale simulation, Multi-component hydrocarbon migration

Abstract

Continental shale oil is a vital alternative resource for oil and gas reserve and production growth in China. However, strong reservoir heterogeneity, widely developed micro-nano pore throats and complex multi-component crude oil properties lead to low crude oil producing degree and restrict efficient large-scale development. Most existing seepage studies are based on single-component assumptions, failing to fully reveal multi-component differential migration, competitive seepage mechanisms and the threshold regulation effect of pore scale. To address this issue, this study builds a pore-scale multi-component seepage model through numerical simulation, divides hydrocarbons into light, medium and heavy components, and systematically analyzes migration characteristics under varying injection flow rates and particle radii. The results show that component properties dominate differential migration and competitive seepage: light components with strong convection and diffusion capacities preferentially occupy dominant seepage channels and gradually compress the flow space of medium and heavy components. Within the range of 1.0-3.0 g/s, injection flow rate has a weak influence on the multi-component distribution pattern and does not alter the relative migration capacity of each component. Pore scale imposes selective regulation with a distinct threshold effect: heavier components are more sensitive to pore tightening, and the inter-component migration capacity gap widens sharply when the throat width shrinks below a critical value of δcr ∈ (5, 10) mm (corresponding to a critical particle radius rcr ∈ (20.0, 22.5) mm and a constriction ratio αcr ∈ (0.10, 0.20)). This study deepens the understanding of multi-component microscopic migration mechanisms of continental shale oil, and provides theoretical support for reservoir producing degree evaluation, development parameter optimization and hierarchical reservoir stimulation

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Published

2026-06-15

Issue

Vol. 13 No. 1 (2026)

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Copyright (c) 2026 Fuqiang Xu, Zhigang Liu, Can Ji, Rubing Han, Yan Liu, Aimin Chen

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How to Cite

1.
Pore-scale Competitive Migration and Selective Regulation of Multi-component Hydrocarbons in Continental Shale Oil: A Phase-field Modeling Study. Int. J. Pet. Technol. [Internet]. 2026 Jun. 15 [cited 2026 Sep. 12];13(1):29-42. Available from: https://www.avantipublishers.com/index.php/ijpt/article/view/1841

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