物料粒径对半自磨机衬板磨损的影响

Effect of particle size on liner wear in semi-autogenous mill

采用数值计算方法分析粒径对半自磨(SAG)机衬板磨损的影响。采用离散单元法(DEM)描述物料运动,采用切向碰撞能量磨损模型(SIEM)预测壁面磨损.结果表明,粒径大小对衬板磨损存在显著影响.粒径增大,衬板磨损亦随之增大;当粒径较小时(如:d=30 mm),磨损增幅尤为明显.提升条的磨损主要在经过底脚区与颗粒发生剧烈碰撞时产生,不同粒径大小下均如此.大颗粒获得的动能要远远大于小颗粒,且相比于小颗粒,大颗粒改变运动状态需要更长的时间,导致剧烈磨损的持续时间亦明显增加.粒径大小对磨损在提升条上的分布无明显影响.

The effect of particle size on liner wear in semi-autogenous grinding(SAG) mills was investigated using a numerical approach. The charge motion was calculated using discrete element method(DEM) and the liner wear was predicted using shear impact energy model(SIEM). The simulation results indicate that the particle size has evident influence on the liner wear. The liner wear increases with the increase of particle size;the increasing rate is evidently larger when the particle size is small(e.g. d=30 mm). The liner wear mainly occurs during the intense collisions in the bulk toe, which is not altered by the particle size. The kinetic energy of the large particles is significantly larger than that of the small particles. The large particles needs longer time to change the motion state compared with the small particles, which leads to longer intense collisions. The particle size has little influence on the distribution of wear on the lifters.