摘要
The effect of CaCO_(3),Na_(2)CO_(3),and CaF_(2) on the reduction roasting and magnetic separation of high-phosphorus iron ore containing phosphorus in the form of Fe_(3)PO_(7) and apatite was investigated.The results revealed that Na_(2)CO_(3) had the most significant effect on iron recovery and dephosphorization,followed by CaCO_(3),the effect of CaF_(2) was negligible.The mechanisms of CaCO_(3),Na_(2)CO_(3),and CaF_(2) were investigated using X-ray diffraction(XRD),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS).Without additives,Fe_(3)PO_(7) was reduced to elemental phosphorus and formed an iron-phosphorus alloy with metallic iron.The addition of CaCO_(3) reacted with Fe_(3)PO_(7) to generate an enormous amount of Ca_(3)(PO_(4))_(2) and promoted the reduction of iron oxides.However,the growth of iron particles was inhibited.With the addition of Na_(2)CO_(3),the phosphorus in Fe_(3)PO_(7) migrated to nepheline and Na_(2)CO_(3) improved the reduction of iron oxides and growth of iron particles.Therefore,the recovery of iron and the separation of iron and phosphorus were the best.In contrast,CaF_(2) reacted with Fe_(3)PO_(7) to form fine Ca_(3)(PO_(4))2 particles scattered around the iron particles,making the separation of iron and phosphorus difficult.
基金
financially supported by the National Natural Science Foundation of China(No.51874017)。
