在选矿成本中,矿石的碎、磨费用通常占40～60％,而其中磨矿费用又占70～90％。因此,如何提高磨矿效率,特别是提高细磨效率乃是选矿的一个重要课题。湖南祁东铁矿系微细粒嵌布的磁-赤铁矿,硬度f=8.8～14.4。根据选矿工艺的要求,入选粒度为94～95％—74微米;粗精矿再磨粒度为97～98％—37微米。在此细度下,采用絮凝-弱磁-离心-再磨絮凝流程,可从品位28％的原 In the dressing costs, ore crushing, grinding costs usually account for 40 to 60%, of which grinding costs account for 70 to 90%. Therefore, how to improve the grinding efficiency, especially to improve the fine grinding efficiency is an important topic of dressing. Micro-grain embedded magnetite hematite from Qidong Iron Mine, Hunan Province, with hardness f = 8.8 ~ 14.4. According to the requirements of beneficiation process, the selected particle size is 94-95% -74 microns; the coarse ore regrinding particle size is 97-98% -37 microns. In this fineness, the use of flocculation - weak magnetic - centrifugal - re-flocculation flocculation process, from the original 28% of the original