精料是高炉冶炼高产优质低耗的基础。入炉品位是高炉精料的重要条件。为了提高入炉矿品位,近年来不少磁选厂上了细筛,有的还建了再磨,使全国磁铁精矿品位1979年平均高达66.5％个别厂超过68％。但是,随着细筛自磨(或再磨)的实现、精矿品位的提高,使选矿球磨台时能力及金属回收率降低了;同时,由于精矿粒度变细、 Concentrate is high-quality low-cost blast furnace smelting smelting basis. Into the furnace grade is an important condition of blast furnace concentrate. In order to improve the quality of ore into the furnace, in recent years a lot of magnetic separation plant on the fine sieve, and some also built and then grinding, so that the average grade of magnetite concentrate in 1979 up to 66.5% individual factory more than 68%. However, with the realization of the fine mesh self-grinding (or regrinding) and the improvement of the quality of the concentrate, the capacity and the metal recovery of the ball milling table are reduced. At the same time, due to the finer particle size of the concentrate,