Dephosphorization mechanism in a roasting process for direct reduction of high-phosphorus oolitic hematite in west Hubei Province,China

Direct reduction-roasted products and final products after magnetic separation, which are reduced from high-phosphorus oolitic hematite in west Hubei Province of China by adding a dephosphorization agent, were investigated by XRD and SEM. The results show that the dephosphorization agent added in the reduction-roasting process can remove phosphorus and promote iron reduction. The dephosphorization agent not only transforms partial phosphorus ores into easy removed solvable phosphate but also breaks the oolitic structure, leading to an easy separation of iron from gangue after fine grinding and magnetic separation in order to remove phosphorus. The grade and recovery of iron also improve due to adding the dephosphorization agent.