In the iron and steel industry, the production of narrow particle size distribution (PSD) for pellet feed making with acceptable liberation of valuables from the iron ore is very difficult. This study has been carried out to achieve desired pellet feed with narrow PSD and maximum liberation of hematite from the iron ore. The iron ores have been collected from three different sources (mines in Karnataka state) and milled. The iron ores and the blend feed samples were analyzed in the Optical Microscope (OM) and Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN) to understand the PSD and percentage of hematite liberation. The new approach is adapted to identify the retention time (RT) of the iron ore in the mill, and the total RT taken for the blend sample in the Bond’s ball mill is considered as the reference grinding time for milling in the Laboratory Ball Mill (LBM). The desired narrow PSD (− 150/+ 10 µm) with acceptable hematite liberation is achieved at an optimal grinding time of 7 min in the LBM.

在钢铁工业中，很难生产用于颗粒饲料的窄粒度分布（PSD），并且可以从铁矿石中释放出有价值的物品。已经进行了该研究以实现具有窄的PSD和最大程度地从铁矿石中释放赤铁矿的所需颗粒饲料。铁矿石已从三种不同来源（卡纳塔克邦的矿山）中收集并进行了研磨。铁矿石和混合饲料样品在光学显微镜（OM）中进行分析，并通过扫描电子显微镜（QEMSCAN）对矿物进行定量评估，以了解PSD和赤铁矿释放的百分比。新方法适用于确定磨机中铁矿石的保留时间（RT），并且将Bond球磨机中混合样品的总RT作为在实验室球磨机（LBM）中进行研磨的参考研磨时间。在LBM中，最佳的7分钟研磨时间可实现所需的窄PSD（-150 / + 10 µm）和可接受的赤铁矿释放。