Experimental study on separation of lumpish coal and gangue using X-ray
Yong Zhang, Hongzheng Zhu, Jinbo Zhu, OU Zhan-bei, Tuo Shen, Jingjing Sun, An'an Feng
Abstract
The recognition of lumpish coal and gangue of different coal sorts was conducted using X-ray technique. Gas coal, fat coal and coking coal were used in this study, and the ash content was found to roughly increase linearly with the density independently of coal sort. Al2O3, SiO2, Fe2O3 and SO3 were detected to be the major oxides for the increase in ash content as the density increased. The gray value of coal was larger than that of gangue and decreased with the increase in thickness and density independently of coal sort and energy zone. The gray value in the high energy zone was found to overlap with that in the low energy zone. Material attribute value (R) was applied for estimating the accuracy of the recognition, and the highest accuracy was given at R = 1.3.