Microstructure Evolution of Ore Particles during Bioleaching Based on X-Ray Micro-Computed Tomography Images

Abstract:

Microstructure of ore particle has significant influence on the efficiency of bio-heap leaching, because it affects such processes as microscale fluid flow, mass diffusivity, bacteria growth, chemical reaction, etc. The micropores and microcracks in ore particles evolve continuously during bioleaching. To obtain crucial quantitative information on structural evolutions, non-destructive techniques become necessary. In this study, a cylindrical ore sample of 3mm diameter was scanned with X-ray micro-CT before and after bioleaching test. The ore sample is a kind of mixed ore that composed of oxide copper and sulfide copper. The CT scanner used is μCT225kvFCB. By using an in-house developed image analysis program based on MATLAB, 3D information about the total porosity, the pore size distribution, the pore connectivity, and the pore fractal dimension of the ore sample before and after bioleaching were calculated and analyzed. The results obtained in this study are promising for a better understanding of microstructure evolution mechanisms on ore particles during bioleaching. Results also show that 3-D image analysis is a powerful technique to characterize the morphological, structural and topological differences due to bioleaching.

• Periodical: Advanced Materials Research (Volume 1130)
• Pages: 325-328
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1130.325
• Online since: November 2015
• Authors: Bao Hua Yang*, Ai Xiang Wu, Xiu Xiu Miao, Hong Bing Liu
• Keywords: 3D Image Analysis, Bioleaching, Micro-Computed Tomography, Microstructure, Ore Particle

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