Abstract: CT (Computer Tomography) technology was used to obtain the sectional images of the upper, middle and lower zones of the solvent leaching column in the leaching process, the self-written Matlab program to estimate the pore fractal dimensions of these images and the main factors leading to the change in the pore structure in the leaching column were analyzed briefly. The results indicate that there is time and spatial variation in the pore structure of the rock-ore bulk media in the dump leaching process, which is related to the transfer and stacking of fine particles under both physical and chemical effects. The pore fractal dimensions decrease with the increase of height before the leaching but increases with the increase of height after the leaching; and the sectional fractal dimensions of the same zone will increase after the leaching when compared with before the leaching, with the increase extent in the lower zone being 19 times that in the upper zone.

Key words: Fractal dimensions, Rock-ore bulk media, Pore structure, CT technology