某难选铁矿石直接还原焙烧磁选研究

对某含铁品位为28.82%, 含磷0.35%的难选铁矿石进行了直接还原焙烧磁选研究。研究了焙烧温度、还原剂用量、焙烧时间、助溶剂用量、磨矿粒度以及磁场强度对直接还原铁品位和回收率的影响。在还原剂用量为30%, 助溶剂QK用量为20%, 焙烧温度为1 200 ℃, 焙烧时间为30 min, 一段磨矿粒度为-43 μm粒级含量达到95%以上, 二段磨矿粒度为-30 μm粒级含量达到100%, 一段磁选场强为111.5 kA/m, 二段磁选场强为95.5 kA/m的条件下, 可以获得品位为90.94%, 回收率为82.67%的直接还原铁。

Direct Reduction Roasting-Magnetic Separation Technique of a Refractory Iron Ore

A process of direct reduction roasting-magnetic separation was introduced to treat a refractory iron ore with an iron content of 28.82% and a phosphorus content of 0.35%. The effects of processing parameters, such as roasting temperature, dosage of reducing agent, roasting time, dosage of fluxing agent, grinding fineness and magnetic field intensity, on the iron grade and recovery of the DRI (direct reduced iron) were investigated. With the reducing agent dosage of 30%, fluxing agent (QK) dosage of 20%, roasting temperature of 1 200 ℃, and roasting time of 30 min, meanwhile, with a grinding fineness of the -43 μm range amounts over 95% for the first stage of grinding, the -30 μm range amounts over 100% for the second stage of grinding, and with a magnetic field intensity of 111.5 kA/m and 95.5 kA/m for the first and the second stage of magnetic separation, respectively, DRI concentrate with a grade and a recovery of 90.94% and 82.67%, respectively, can be obtained.