高磷鲕状铁矿氧化球气基还原⁃磁选提铁降磷研究

Iron Recovery and Dephosphorization of Oxidized Pellets of High⁃Phosphorus Oolitic Iron Ore Using Gas⁃Based Reduction and Magnetic Separation Technology

以某高磷鲕状铁矿氧化球为试样,研究了气基还原⁃磁选生产粉末还原铁工艺。以CaCO_(3)为脱磷剂时,考察了还原气体总流量、还原温度以及还原时间对提铁降磷的影响,发现调整上述条件,均不能获得合格的粉末还原铁;以Na_(2)CO_(3)为脱磷剂时,考察了还原温度以及Na_(2)CO_(3)用量对提铁降磷的影响,结果表明,在Na_(2)CO_(3)用量15%、H_(2)与CO流量分别为3.75 L/min和1.25 L/min、1100℃下还原180 min,获得了铁品位96.55%、铁回收率94.99%、磷含量0.08%的优质粉末还原铁。

With the oxidized pellets of a high⁃phosphorus oolitic iron ore as the raw material,production of powdery reduced iron by adopting gas⁃based direct reduction and magnetic separation was studied.Using CaCO_(3) as the dephosphorization agent,the effects of total gas flow rate,temperature and time on iron recovery and dephosphorization performance were investigated.It is found that qualified powdery reduced iron was still unobtainable after the adjustment of above conditions.With Na_(2)CO_(3) as the dephosphorization agent,the effects of reduction temperature and Na_(2)CO_(3) dosage on iron recovery and dephosphorization performance were also investigated.It is found that with Na_(2)CO_(3) dosage of 15%,flow rates of H_(2) and CO at 3.75 L/min and 1.25 L/min,respectively,a 180 min⁃reduction process at 1100℃can result in a high⁃quality powdery reduced iron with Fe grade of 96.55%,Fe recovery of 94.99%and P content of 0.08%.