多级配球降低半自磨中顽石积累及改善磨矿效果试验  

Hard Rock Accumulation Decrease and Grinding Effect Improvement in Semi Autogenous Grinding by Multi-Stage Ball Distribution

作　　者：武煜凯 肖庆飞[1,2] 高志勇 Wu Yukai;Xiao Qingfei;Gao Zhiyong(School of Land Resource Engineering,Kunming University of Science and Technology,Kunming 650093,China;State Key Laboratory of Automatic Control Technology of Mining and Metallurgy Process,Beijing 100070,China;School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]矿冶过程自动控制技术国家(北京市)重点实验室,北京100070 [3]中南大学资源加工与生物工程学院,湖南长沙410083

出　　处：《稀有金属》2022年第5期673-680,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金面上项目(51774157);矿冶过程自动控制技术国家(北京市)重点实验室开放基金项目(201905)资助。

摘　　要：针对新疆某铜镍矿半自磨机顽石积累严重、磨矿效果差的问题,采用离散元法(DEM)模拟仿真实验模拟分析不同级配钢球对顽石的碰撞能量分布及利用率,并在实验室进行半自磨机磨矿循环试验验证。研究结果表明:在此试验中,多级配球在能量利用率方面优于单一球径及偏大级配,多级配球可在提供与偏大级配相同冲击力的情况下增加碰撞次数,从而使能量分布更加合理,且改善磨矿效果的同时降低了衬板磨损;推荐级配钢球较现场级配及偏大级配切向碰撞能量利用率分别提高了8.88%和1.38%,法向碰撞能量利用率分别提高了3.66%和0.92%,推荐级配对衬板的碰撞能量较偏大级配降低了1061.84 J;验证试验中推荐级配顽石产率较现场级配及偏大级配分别降低了4.19%和3.36%,-74μm产率分别提高了4.80%和2.24%。从理论分析及试验验证多级配球可有效降低半自磨顽石积累并改善磨矿效果。Autogenous mill,as one of the important equipment in grinding operation,has the characteristics of short process and small amount of equipment.The particle size of+100 mm plays a very important role as grinding medium in autogenous mill.The particle size of-80~+20 mm,as the critical particle size,does not participate in the grinding process of autogenous mill,and will block the discharge grid of autogenous mill,which belongs to"hard grinding particles",and is easy to produce hard rock accumulation.In this paper,the capacity ofФ5.5 m×1.8 m(D×L)semi autogenous mill was only 900~1000 t·d^(-1).The problem of hard rock accumulation seriously affected the capacity of the mill.Therefore,it was of great significance to explore the collision energy distribution between different grinding medium gradations of semi autogenous mill and ore,and improve the energy utilization rate of crushed ore for energy saving and consumption reduction of mine.Based on this,the energy utilization of the semi autogenous mill and the collision energy distribution of the grinding medium were analyzed by using the discrete element method(DEM),and the grinding cycle of the semi autogenous mill in the laboratory was analyzed,the reliability of the simulation was verified by experiments.DEM was a numerical technique used to predict the behavior of collision dominated particle flows.Each particle in the flow was tracked and all collisions between particles and between particles and boundaries were modelled.The particles were allowed to overlap and the extent of overlap was used in conjunction with a contact force law to give instantaneous forces from knowledge of the current positions,orientations,velocities and spins of the particles.The results showed that the energy utilization rate of multi-stage ball was better than that of single ball diameter and larger grading.Multi stage ball could increase the number of collisions under the condition of providing the same impact force as the larger grading,so as to make the energy distribution more re

关 键 词：多级配球 半自磨 顽石 碰撞能量分布 离散元 磨矿效果 

分 类 号：TD952[矿业工程—选矿]