ABSTRACT In a recent study by the authors, green pellets motion behavior and interactions among themselves and with the equipment during classification were successfully modeled through simulations with the discrete element method using the Hertz-Mindlin with JKR contact model. The present work initially deals with a parametric simulation study of five important variables in a roller screening operation, namely, gap between the rolls for removal of undersize, rolls rotational frequency, rolls diameter, deck angle, and throughput. The effect of the individual variables and their interactions are analyzed through factorial simulation experiments. Following these initial simulations, a response surface methodology coupled to the application of multiobjective optimization was used to identify a setting of the various variables that would allow improving classification performance. Such results led to a proposition of a new configuration for the roller screen, which consisted in a significant reduction in roll diameter and deck slope, an increase in rolls rotational frequency and a reduction in undersize gap. Simulations predicted, for the studied material, an increase in fines removal efficiency from 91.4% for the base case configuration to 97.1% for the optimized case, with a reduction to one-third the contamination of the on-size material, and a moderate increase in the efficiency of properly sized material reporting to the on-size product. Although at the expense of a modest increase in loss of properly sized pellets to the oversize, such optimized configuration is also predicted to be significantly more robust to surges in the feed than the base case.

中文翻译：

---

通过统计分析和离散元模拟改进生铁矿球团的滚筒筛分

摘要 在作者最近的一项研究中，通过使用具有 JKR 接触模型的 Hertz-Mindlin 的离散元方法进行模拟，成功地对生球团运动行为以及它们之间以及与设备在分类过程中的相互作用进行了建模。目前的工作最初涉及对辊筛选操作中五个重要变量的参数模拟研究，即用于去除筛下尺寸的辊之间的间隙、辊旋转频率、辊直径、甲板角度和吞吐量。通过因子模拟实验分析各个变量及其相互作用的影响。在这些初始模拟之后，响应面方法与多目标优化的应用相结合，用于确定各种变量的设置，以提高分类性能。这样的结果导致了一种新的滚筒筛网配置的提议，其中包括显着减小辊直径和甲板坡度、增加辊旋转频率和减小尺寸过小的间隙。模拟预测，对于所研究的材料，细粉去除效率从基本情况配置的 91.4% 增加到优化情况的 97.1%，尺寸上材料的污染减少到三分之一，并且适度增加正确尺寸的材料报告给尺寸产品的效率。