铁矿石是炼铁的主要原料,但并非任何矿石都适于直接送去冶炼。含铁量低的铁矿——贫铁矿,就必须先经过选矿,使矿石中铁矿物和不需要的矿物(通称脉石矿物)分离,选得含铁品位较高的精矿,方能冶炼。我国含铁量在40％以下的贫赤铁矿,在铁矿貯量中占很大的比例。这种铁矿是弱磁性的,不能象磁铁矿那样用通常的磁选机来选矿,也就是根据磁铁吸引原理,来把铁矿 Iron ore is the main raw material for ironmaking, but not all ores are suitable for direct delivery to smelting. The iron ore with low iron content, poor iron ore, must first undergo beneficiation to separate iron minerals and unwanted minerals (commonly referred to as gangue minerals) from the ore, and select concentrates with higher iron grades to be able to smelt . China’s lean hematite with iron content below 40% accounts for a large proportion of iron ore reserves. This kind of iron ore is weakly magnetic and cannot be processed by conventional magnetic separators like magnetite, that is, according to the principle of magnet attraction.