磨矿介质运动状态对锡石多金属硫化物的选择性磨矿的影响

磨矿是实现有用矿物与脉石矿物解离的主要过程，不同矿物之间力学性质不同，要求磨矿时具有选择性。介质运动状态对矿石选择性磨矿有决定性影响，尤其脆性矿物与硬度较大的矿物共生时，介质运动状态的调整尤为重要。我国西南地区的锡矿床中是我国锡资源的聚集地，矿石中既含有脆性矿物锡石也含硬度较大的硫铁矿和石英。针对锡石多金属硫化矿嵌布粒度细，磨矿过程中脆性矿物易过粉碎这一问题，研究了矿石在不同的磨矿条件（介质形状、转速、磨矿时间和磨矿浓度）的选择性磨矿行为。研究结果表明：球体介质对于矿石具有较强的冲击破碎力，会对脆性矿物产生过粉碎，不利于后续的选矿作用，添加柱体介质能改善这一现象；提高磨矿浓度和保持较低磨机转速可以改善介质的运动状态，减少冲击破碎作用，增加介质对矿物的研磨作用，避免矿石中产生较多的微细粒，能够产生较好的选择性磨矿作用，为后续的选矿提供有利条件。

Effect of the state of grinding media on the selective grinding of cassiterite polymetallic sulfides

Grinding is the main process to realize the dissociation of useful minerals and gangue minerals. Different minerals have different mechanical properties, which require selectivity when grinding. The state of media movement has a decisive influence on the selective grinding of ore, especially when brittle minerals and harder minerals coexist, the adjustment of the media movement state is particularly important. The tin deposits in southwestern are the gathering places of tin resources in our country. The ore contains both brittle mineral cassiterite and harder pyrite and quartz. Aiming at the problem that the cassiterite polymetallic sulfide ore is embedded with fine grain size and brittle minerals are easy to pass through the fans during the grinding process, the choice of ore under different grinding conditions (media shape, speed, grinding time and grinding concentration) is studied. The research results show that: the spherical medium has a strong impact and crushing force on the ore, and it will over-crush the brittle minerals, which is not conducive to the subsequent beneficiation effect. Adding the cylindrical medium can avoid this phenomenon; increase the grinding concentration and keep the mill speed at the low speed are good for selective grinding. Because the low speed of the mill can change the motion state of the medium, reducing the crushing effect, increase the grinding effect of the hard minerals, avoid the production of more fine particles in the grinding. These approach can produce better selective grinding effect, and provide favorable conditions for subsequent beneficiation.