Evaluation of multiple-scale 3D characterization for coal physical structure with DCM method and synchrotron X-ray CT

Area of Science:

• Earth Science
• Materials Science
• Geology

Background:

• Understanding coal's microscopic physical structure is crucial for optimizing coal conversion and methane extraction.
• Nondestructive characterization methods are essential for preserving sample integrity.

Purpose of the Study:

• To investigate the multiscale physical structure of coal using synchrotron-based multiple-energy X-ray CT.
• To quantitatively characterize multiscale compositional distributions using a data-constrained modeling (DCM) approach at different spatial resolutions.

Main Methods:

• Synchrotron-based multiple-energy X-ray Computed Tomography (CT) was employed.
• Two different spatial resolutions were utilized for imaging.
• A data-constrained modeling (DCM) approach was applied for quantitative analysis.

Main Results:

• Volume fractions for coal matrix, pores, and mineral compositions were determined at two resolutions.
• Differences in computed volume fractions between resolutions were minimal (<0.3% for matrix/pores, <0.17% for minerals).
• The DCM approach demonstrated accuracy in accounting for sub-resolution compositional details.

Conclusions:

• The DCM approach accurately characterizes coal's multiscale physical structure and composition.
• It enables effective analysis of larger coal samples at lower resolutions with minimal loss of detail.
• This method supports advancements in coal conversion and coal-bed methane extraction technologies.