Morphological characterization of crushed coal gangue by micro X-ray computed tomography scanning

ABSTRACT

To accurately estimate the separation effects and breakage characteristics of coal and gangue particles (CGPs), it is of great significance to understand the meso-morphologies of CGPs and their correlations with different crushing conditions. In the present work, the impact crushing tests were conducted to obtain the effects of sizes, gangue mixture ratios, and crushing velocities on the fractal characteristics of the crushed PSD characteristics, using an in-house designed device. Then, X-ray computed tomography (XCT) scanning with different resolutions was conducted on uncrushed and crushed CGPs, followed by a series of image processing and analysis procedures. Finally, the effects of different impact velocities on the evolution of morphological parameters, the fracture ratios, and the fractal fragmentation characteristics were investigated using different image processing algorithms. Results show that many factors such as the energy consumption, the source of raw ores, the impact velocity, and the feeding particle size should be considered to design an optimal crushing scheme for best crushing effects.

KEYWORDS:

• Coal and gangue particles
• breakage characteristic
• X-ray computed tomography
• fractal dimension
• meso-morphological parameters

Additional information

Funding

This research is funded by the China Postdoctoral Science Foundation [2018M630676] and the National Natural Science Foundation of China [Nos. 51779222, 51675521, and 51579221], Zhejiang Basic Public Welfare Research Program [No. LHZ19E090002] and Open Foundation of Shandong Province Key Laboratory of Mine Mechanical Engineering [No.2019KLMM105]. Appreciation is extended to Prof Lin CL and Miller JD for assistance in the XCT scanning experiments.