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过程工程学报 ›› 2022, Vol. 22 ›› Issue (2): 232-239.DOI: 10.12034/j.issn.1009-606X.221051

• 研究论文 • 上一篇    下一篇

基于液桥效应圆筒制粒机的铁矿粉制粒机理研究

龚曙光1*， 廖明1， 卢兴福2， 左志坚1， 刘克俭2   

  1. 1. 湘潭大学机械工程学院，湖南 湘潭 411105 2. 国家烧结球团系统装备研究中心，湖南 长沙 410000
  • 收稿日期:2021-02-12 修回日期:2021-04-12 出版日期:2022-02-28 发布日期:2022-02-28
  • 通讯作者: 龚曙光 gongsg@xtu.edu.cn
  • 作者简介:龚曙光(1964-)，男，湖南省涟源市人，博士，教授，研究方向为CAE技术的理论与应用研究，E-mail: gongsg@xtu.edu.cn.
  • 基金资助:
    基于物质点法粉体颗粒机械混匀的分析方法及优化研究

Study on granulating mechanism of iron ore powder in drum mixer based on liquid-bridge effect

Shuguang GONG1*,  Ming LIAO1,  Xingfu LU2,  Zhijian ZUO1,  Kejian LIU2   

  1. 1. School of Mechanical Engineering, Xiangtan University, Xiangtan, Hunan 411105, China 2. National Sintering and Pelletizing Equipment System Engineering Research Center, Changsha, Hunan 410000, China
  • Received:2021-02-12 Revised:2021-04-12 Online:2022-02-28 Published:2022-02-28

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摘要： 针对圆筒制粒机中存在有不同量级粒径颗粒的制粒问题，本工作对现有的液桥力计算式进行了修正，建立了相对应的离散元模型，通过实验测试与仿真相结合，探讨了修正系数对颗粒运动的影响，得到了修正系数以0.6适宜；以铁矿粉混合料的堆积角为参考，通过仿真和实验测试得到了混合料的物性参数，以此为基础，探讨了铁矿粉混合料颗粒的运动规律与团聚机理及其团聚体的分布，结果表明，团聚体颗粒的自旋速度越大、所受剪切力越小，则越有利于制粒；团聚体粒径沿圆筒的径向呈现先增大后减少的变化，且在靠近混合料表层下存在一个“高效制粒区”，在该区域团聚体的粒径最大、剪切力最小、自旋速度较大，同时建议可采用颗粒碰撞频率或能量损失作为判据来终止颗粒的团聚，以达到节能降耗的目的，所得结论可为铁矿粉圆筒制粒机的研发提供设计依据。

关键词: 圆筒制粒机, 离散元法, 液桥力, 制粒, 铁矿粉, 团聚体

Abstract: To solve the problem of granulating with different magnitude sizes of particles in the drum mixer, the existing calculation formula of liquid bridge force was modified and the corresponding discrete element model was established in this work. Through the combination of experimental test and simulation, the influence of the correction coefficient on particle motion was discussed, and the correction coefficient of 0.6 was found to be suitable. Taking the accumulation angle of the iron ore powder mixture as a reference, the physical property parameters of the mixture were obtained through simulation and experimental tests. On this basis, the movement law, agglomeration mechanism, and the distribution of agglomerates of iron ore powder mixture were discussed. The results showed that the larger the spin velocity and the smaller the sheer force of agglomerate powder, the more favorable the granulation was. The particle size of agglomerate increased first and then decreased along the radial direction of the cylinder, and there was an "efficient granulation zone" under the surface layer of the mixture, in which the particle size of agglomerates was the largest, the shear force was the least and the spin velocity was high. It was suggested that the collision frequency or energy loss of the agglomeration particle can be used as the criterion to stop the agglomeration of particles, to achieve the purpose of energy-saving. The conclusions can provide a design basis for the research and development of iron ore powder drum mixer.

Key words: Drum mixer, Discrete element method, Liquid bridge force, Granulation, Iron Ore powder, Agglomerate