Data-constrained modelling of an anthracite coal physical structure with multi-spectrum synchrotron X-ray CT

► A DCM model with multi-spectrum synchrotron X-ray CT is used to characterise an anthracite coal physical structure. ► This model enables detection of mixed composition distributions at length scales smaller than X-ray CT resolution. ► The 3D physical structure of the sample is obtained and the partial volume effect is addressed with DCM. ► Voids and some minerals at length scales smaller than X-ray CT resolution have been detected and displayed. A data-constrained modelling (DCM) approach with multi-spectrum synchrotron X-ray CT has been used to characterise the physical structure of Yangquan coal sample. Three sets of X-ray CT data have been acquired with monochromatic beam energies at 14, 18, and 30keV respectively. A DCM approach is used to derive compositional volume fractions on each voxel, by minimising the differences between the expected and CT reconstructed absorption coefficients with a nonlinear optimization algorithm. Voxel based 3D compositional maps are generated with colours and intensities representing compositions and volume fractions respectively. The results are relevant in quantitative modelling of coal-bed gas transportation and coal processing.