Research Progress on Evolution of Coal-Water Contact Angles and Mechanisms of Wettability Regulation: From Theoretical Foundations to Field Applications

Yingdan Liang; Liguo Liu

doi:10.54691/x38bv932

Authors

Yingdan Liang
Liguo Liu

DOI:

https://doi.org/10.54691/x38bv932

Keywords:

Gas-bearing atmosphere; Coal-water contact angle; Wettability; Gas adsorption; Coal dust control.

Abstract

The gas present in coal seams can alter the coal-water interface properties through adsorption, yet a systematic understanding of its underlying mechanisms remains lacking. This review systematically examines the factors influencing coal wettability in gas-bearing atmospheres, with a focus on the regulatory effects of physicochemical properties of coal—such as coal rank, pore structure, mineral composition, and functional groups. It further elucidates the mechanisms by which strongly adsorbing gases like CH₄ and CO₂, as well as weakly adsorbing gases such as N₂ and He, affect the coal-water interface. The practical applications of related theories in field settings, such as optimizing coal seam water injection processes and improving dust suppression efficiency, are also summarized. This study aims to provide a theoretical foundation for advancing the understanding of coal-water wetting mechanisms in gas-bearing environments and to support the optimization of related engineering practices, thereby contributing to safer and greener coal mining operations.

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