Applications and advances in characterizing pore-interface structures in coal using small angle scattering...

Area of Science:

• Geology
• Materials Science
• Physical Chemistry

Background:

• The multiscale pore-fracture interface in coal dictates coalbed methane (CBM) storage and CO2 geological storage efficiency.
• Understanding coal-fluid interactions is vital for optimizing energy and environmental technologies.

Purpose of the Study:

• To systematically review small angle scattering (SAS) technology for analyzing coal matrix pore interfaces.
• To focus on the application of SAS in understanding coal-fluid interfaces, including geometry, properties, and dynamics.
• To provide micromechanical support for CBM development and carbon capture, utilization, and storage (CCUS).

Main Methods:

• Small Angle Scattering (SAS) for pore system quantification.
• In-situ SAS for real-time tracking of interface dynamics under external fields.
• Contrast-Matching Small-Angle Neutron Scattering (CM-SANS) for fluid accessibility visualization.
• Time-resolved small angle scattering for dynamic structural response capture.
• Multi-scale and multi-dimensional data fusion.

Main Results:

• SAS can nondestructively quantify the entire pore system, including closed pores.
• Coal type and tectonic stress significantly influence closed pore distribution.
• SAS provides parameters for describing interface complexity and its correlation with coal composition.
• In-situ SAS tracks coal matrix responses to gas adsorption, stress, and pyrolysis.

Conclusions:

• SAS is a powerful tool for characterizing coal pore structure and coal-fluid interfaces.
• Understanding these interfaces is key to advancing CBM development and CCUS technologies.
• This review offers insights into advanced SAS techniques for energy and environmental applications.