Fractal analysis of granular ore media based on computed tomography image processing

The cross-sectional images of nine groups of ore samples were obtained by X-ray computed tomography(CT) scanner. Based on CT image analysis, the fractal dimensions of solid matrix, pore space and matrix/pore interface of each sample were measured by using box counting method. The correlation of the three fractal dimensions with particle size, porosity, and seepage coefficient was investigated. The results show that for all images of these samples, the matrix phase has the highest dimension, followed by the pore phase, and the dimension of matrix-pore interface has the smallest value; the dimensions of matrix phase and matrix-pore interface are negatively and linearly correlated with porosity while the dimension of pore phase relates positively and linearly with porosity; the fractal dimension of matrix-pore interface relates negatively and linearly with seepage coefficient. Larger fractal dimension of matrix/pore interface indicates more irregular complicated channels for solution flow, resulting in low permeability.