带式焙烧机布料筛分系统离散元仿真研究

Research on segregation and screening of traveling grate machine

针对带式焙烧机球团生产过程中存在料层透气性不均的问题,采用离散元模型对移动胶带-宽胶带-辊筛组成布料筛分系统的布料和筛分性能进行仿真研究,详细分析布料筛分系统中的工艺参数对布料均匀性和粒度分布的影响,旨在改善带式焙烧机球团生产过程中料层透气性。由于球团在带式焙烧机内相对台车处于静止状态,整个生产过程中不断与穿过料层的气流进行能量交换,因此料层透气性是影响球团矿产、质量的关键因素,而生球布料均匀性和粒度分布直接决定了料层透气性。研究结果表明:通过建立来料胶带有效宽度与移动胶带运行参数间的函数关系、适当降低宽胶带运行速度能够有效提高生球布料均匀性,并通过调节筛辊转速可以实现最佳布料和筛分效果。

In view of the problems of uneven bed permeability existing in the production process of traveling grate,the discrete element model is adopted to simulate the feeding and screening performance of the feeding and screening system made up of the mobile belt conveyor,wide belt conveyor and roller screen,and the influences of process parameters of the system on the uniformity of feeding and particle size distribution are analyzed in detail in order to improve bed permeability in pellet production by traveling grate machine.As pellets are in a static state relative to the pallet in the traveling grate machine,they exchange energy with the air flowing constantly through the material bed in the whole production process.Therefore,the bed permeability is the key factor affecting the quality of pellets,and the uniformity of green pellets distribution and particle size distribution determine the bed permeability.The research result shows that,the distribution uniformity of the green pellets can be improved by establishing the function between the effective width of the feeding belt and the operating parameters of the moving belt conveyor and by properly reducing the running speed of the wide belt.By adjusting the rotation speed of the roller screen,the optimal feeding and screening effect can be achieved.