煤矸冲击破碎速度的影响因素研究

为给煤和矸石的选择性破碎分选及破碎装置设计提供理论指导，采用离散元法对煤矸冲击破碎速度的影响因素进行研究。以材料的抗压测试为校核依据，建立了单颗粒煤矸冲击破碎离散元模型，并在自制的冲击实验台上开展单颗粒冲击破碎试验，验证离散元模型的正确性。利用建立的离散元模型研究了煤矸材料参数及圆柱形破碎杆半径对煤矸冲击破碎速度的影响规律，研究结果表明：煤矸冲击破碎速度随材料抗压强度的增加成线性增加，随弹性模量和密度的增加成幂函数形式减小；圆柱形破碎杆的半径越小，越有利于抗压强度有一定差异的煤和矸石的选择性破碎分选。

Study on Influence Factors of Impact Crushing Speed of Coal Rejects

In order to provide theoretical guidance to the design of a selective crushing separation and crushing device for coal and coal rejects,a discrete element method was applied to study the influence factors of the coal reject impact crushing speed.Taking the material compressive measurement as check basis,an impact crushing discrete element model of a single particle coal reject was established.A single particle impact crushing test was conducted on the self made impact testing rig and the correctness of the discrete element model was verified.The discrete element model established was applied to study the coal rejects material parameters and the cylindrical crushing bar radius to the influence law of the coal rejects impact crushing speed.The study results showed that with the compressive strength of the material increased,the coal rejects impact crushing speed would be increased in linear,with the elastic modulus and density increased,the power function form of the coal rejects impact crushing speed would be reduced.The smaller radius of the cylindrical crushing bar,the more favorable the selective crushing separation of the coal and coal rejects with certain different compressive strengths would be.