Distribution Characteristics of Phosphorus in the Metallic Iron during Solid-State Reductive Roasting of Oolitic Hematite Ore

Abstract

The distribution characteristics of phosphorus in the metallic iron, and the reduction behaviors of hematite and fluorapatite during solid-state reductive roasting of a phosphorus-rich (1.3 mass%) oolitic hematite ore were investigated in the temperature range of 900°C–1200°C. Experimental results show that phosphorus in the iron is present in the forms of αFe and Fe3P, resulted from the simultaneous reduction of fluorapatite and hematite at temperatures up to 1100°C. The phosphorus content in the metallic iron particles decreases from the edge to the center in the pellet cross-section. For the aim of phosphorus removal, the selective reduction of hematite and fluorapatite should be achieved; while for the enrichment of phosphorus as ferrophosphorus, the reduction of fluorapatite, and affinity of P2 and Fe should be guaranteed. These findings could provide guidance for technique development for the utilization of phosphorus-rich oolitic iron ores via pyro-methods.