尾矿细粒化是矿业发展趋势,细粒尾矿的粒径分布对尾矿宏观力学特性及坝体稳定性具有重要影响。采用筛分法和沉降法,对82个尾矿试样进行了颗分试验,建立了细粒尾矿粒径分布的Weibull函数模型。试验结果表明:细粒尾矿粒径呈“细多粗少”的分布规律,这种规律服从Weibull分布,可以用Weibull分布对粒径分布进行描述和外推预测;传统分形模型中假设每级粒度的破碎率为常数与实际情况不符,Weibull分布可以看作对分形模型误差的一种修正;在破碎过程中,粒径的概率密度分布会出现峰值,这个峰值不断向粒径小的方向偏移,最终形成“细多粗少”的分布特点。研究结果有助于磨矿工艺的改进,并可以为土工试验做出科学的级配方案提供参考。
Along with the progress of fine-graining, the rule of particle size distribution in fine-grained tailings becomes increasingly significant as it has an important influence on tailings' macro mechanical properties and stability. In this paper, we analyzed 82 tailing samples with the sieving and the settlement methods, and set up a Weibull function model for fine-grained tailings. The experimental results show that the number of fine particle is far more than that of coarse particle, and this distribution character can be described and speculated by Weibull distribution. Weibull distribution could be regarded as a fractal model to a certain extent and it considers the change of crushing rate that tradition fractal model doesn't consider. In the process of crushing, the peak of probability density distribution shifts towards the direction of fine particles, and this explains how the distribution character of fine-grained tailings forms. It's hoped that the research findings provide references for granularity theory and ore grinding process.