Effects of Combined Dephosphorization Agents on Reduction Roasting-Magnetic Separation of High Phosphorus Iron Ore

doi:10.12068/j.issn.1005-3026.2022.03.016

Abstract

Abstract: In view of the problems such as high cost and large amount of dephosphorization agents in the process of dephosphorization by reduction roasting of high phosphorus iron ore， to better develop and utilize high phosphorus iron ore， the effect of combined dephosphorization agents on iron improvement and dephosphorization of high phosphorus iron ore was studied via reduction roasting-magnetic separation process. X-ray diffraction(XRD)and scanning electron microscope-energy dispersive spectroscopy(SEM-EDS)were used to reveal the mechanism of dephosphorization. The results showed that adding 13% CaCO₃ and 2% Na₂CO₃ as a combined dephosphorization agent can replace the traditional dephosphorization agent， and good dephosphorization effect is obtained. Under the recommended experimental conditions， powdery reduced iron with iron grade of 93.25%， iron recovery of 90.75%， phosphorus content of 0.09%， and dephosphorization of 91.46%can be obtained when iron grade is 55.58% and phosphorus content of raw ore is 0.57%. The added combined dephosphorization agent not only promotes the transformation of phosphorus components in the iron oxides into calcium phosphate， and makes the boundary between metallic iron particles and calcium phosphate distinct， but also prevents the formation of hercynite and fayalite， which is difficult to reduce. Finally， the deep removal of phosphorus and the effective recovery of iron are realized.

Key words: high phosphorus iron ore; reduction roasting; magnetic separation; combined dephosphorization agent; dephosphorization

CLC Number:

TD925

WU Shi-chao， SUN Ti-chang， KOU Jue， CHEN Ze-kun. Effects of Combined Dephosphorization Agents on Reduction Roasting-Magnetic Separation of High Phosphorus Iron Ore[J]. Journal of Northeastern University(Natural Science), 2022, 43(3): 423-430.

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