某贫细鲕状赤铁矿直接还原-磁选新工艺

针对贵州某贫细鲕状赤铁矿难选的特点, 开发了直接还原焙烧-磁选新工艺。采用箱式电阻炉加热, 煤基直接还原工艺, 经磨矿-磁选, 得到高品位的铁精粉, 为开发利用细粒嵌布复杂低品位铁矿提供了理论依据。通过L₉(3⁴)正交试验, 确定试验的最佳条件为还原剂用量40%、助还原剂用量15%、焙烧温度1 050 ℃、焙烧时间180 min、磨矿浓度50%、磨矿产品粒度在-0.037 mm粒级含量达90%以上, 磁选场强为112 kA/m。在最佳条件下可得到TFe品位为90.80%、回收率为89.58%、且有害杂质含量少的铁精粉。该工艺所得高品位铁精粉可代替废钢直接作为电炉炼钢的原料。

Beneficiation of Microfine Low-grade Oolitic Hematite Ore by Direct Reduction-Magnetic Concentration Process

To beneficiate a refractory poor microfine oolitic hematite ore from Guizhou,a new technique of direct reduction-magnetic separation was developed.A coal-based direct reduction process was introduced to treat the raw ore heated using chamber electric furnace,then,after grinding and magnetic separation,iron powder with high grade can be synthesized.This work provides a theoretical foundation for exploitation and utilization of finely-disseminated complex low-grade iron ore.According to the L9(34) orthogonal ...