Jiancheng He, Shijie Lu, Qiheng Zhu, DuboWang, Xiaoxu Sun, Jianchao Yao
Published in Proceedings of the IMPC2020 Congress, SAIMM
Tower mill is considered to have a better regrinding and fine grinding effect compared with ball mill, and its application is much broader. The spiral agitator of the tower mill is driven by the motor. Media inside the mill is under the combined actions ofthe spiral mechanism, the cylinder, and media nearby, and these parameters are key factors affecting the grinding effect. However, it is not possible to obtain detailed information of kinematic law of media based only on traditional laboratory experiments, let alone the relationship between parameters of kinematic law of media and grinding effect.Experimentation is the only way to develop industrial equipment. However, this is time-consuming and costly, which hampers the further research of the tower mill’s grinding mechanism.
The paper selects two structural parameters (gap between the edge of the spiral agitator and the cylinder wall, ratio between the diameter of cylinder and that of the spiral shaft.) and three operating parameters (diameter of media, filling ratio, the speed at the edge of the spiral agitator) as variables to do an orthogonal designed experiment of five factors, four levels, and thereby obtaining change law of grinding indicators of different parameters. Experimental equipment may besimplified to enable an applicable simulation strategy.
Simulation based on a discrete element method is conducted to obtain the change law of the speed of media, collision frequency, normal force, and radial force. The relational curve between parameters of kinematic law of media and energy consumption of grinding is clarified, and key factors affecting grinding efficiency are determined. Those factors will be used for optimising the design and operating process. The research result of this paper obtained from laboratory experiments and computer simulation provides data support and theoretical bases, and has directive meaning and applicable value for tower mill’s optimisation and large-sized design.
Tower mill, discrete element method, kinematic law of media, energy consumption of grinding
The authors would like to thank all colleagues in the BGRIMM grinding engineering group for their help and support during the lab test.This work has been supported by grants from the National Natural Science Foundation of China (No. 51674033,51604027)
Jiancheng Heab,Shijie Luab*, Qiheng Zhuab, DuboWangab,Xiaoxu Sunab, Jianchao Yaoab
aBeijing General Research Institute of Mining and Metallurgy Beijing 100160 China.
bBGRIMM Machinery ＆Automation Technology Co., Ltd. Beijing 100160 China.