煤和矸石颗粒冲击破碎概率差异的分形行为

Impact crushing probability difference between coal and gangue particles based on fractal theory

为揭示煤和矸石颗粒冲击破碎概率差异的内在机理,以冲击破碎概率分形模型为基础,对3个矿区的矸石颗粒进行冲击破碎实验,并与相同矿区内煤颗粒的冲击破碎实验结果进行比较。研究结果表明：粒度在50-100 mm内的矸石颗粒冲击破碎概率与冲击速度在对数坐标中呈线性关系,符合其分形模型;对同一矿区,由于煤和矸石颗粒的来源和物理机械性质不同,矸石颗粒的分形维数和破碎常数均小于煤颗粒的分形维数和破碎常数;在相同冲击速度下,矸石颗粒的冲击破碎概率小于煤颗粒的冲击破碎概率,并且存在最优冲击速度使二者的冲击破碎概率差值最大。

In order to reveal the intrinsic mechanism of the impact crushing probability difference between coal and gangue particles, the impact crushing experiments for gangue particles in three mines were carried out to make a comparison with the impact crushing data for coal particles in the same mine. The results show that the impact crushing probability of gangue particles whose granularity is between 50 mm and 100 mm has linear relation to the impact velocity on the logarithmic coordinate, which indicates that the fractal model of impact crushing probability is suitable for gangue particles. For coal and gangue particles in the same mine, the fractal dimension and crushing constant of gangue particles are both smaller than those of coal particles due to the differences of the source and mechanical properties. With the same impact velocity, the impact crushing probability of gangue particles is less than that of coal particles, and there is an optimum impact velocity which makes the impact crushing probability difference between coal and gangue particles have a maximum value.