High grade iron ore resources are becoming depleted in Brazil, with relatively low-grade ores requiring more intensive comminution for proper liberation of iron minerals, followed by upgrading. Comminution circuits that have been frequently used in the Brazilian iron ore industry in preparation of high-grade iron ores consist of multiple crushing stages followed by ball milling and are known for being highly complex and capital-intensive installations. This work assesses the potential suitability of autogenous (AG) and semi-autogenous (SAG) milling through an extensive pilot plant campaign carried out with itabirite iron ores. The effects of ore type, feed size distribution, circuit configuration (open or closed-circuit and two-stage or single-stage), mode of grinding (AG or SAG), ball load, use of pebble crushing as well as of full secondary pre-crushing have been investigated. The results demonstrate both the technical feasibility and energy efficiency of such an alternative for itabirite comminution circuits.

巴西的高品位铁矿石资源正在枯竭，相对低品位的矿石需要更密集地粉碎才能适当释放铁矿物质，然后进行提质。在巴西铁矿石工业中经常用于制备高级铁矿石的粉碎回路包括多个破碎阶段，然后进行球磨，并且众所周知，其安装高度复杂且需要大量资本。这项工作通过对黄铁矿进行广泛的试验工厂活动，评估了自生（AG）和半自生（SAG）铣削的潜在适用性。矿石类型，进料粒度分布，回路配置（开路或闭路以及两级或单级），磨削模式（AG或SAG），球负荷，已经研究了使用卵石破碎以及完全二次预破碎的方法。结果表明，这种替代品对伊比石粉碎电路具有技术可行性和能源效率。