Effect of Dephosphorization Agent on Gasification and Dephosphorization of High Phosphorus Iron Ore Pellets

The development and utilization of high-phosphorus iron ore are restricted due to its high content of phosphorus.The occurrence state of phosphorus in high-phosphorous iron ores had been investigated by XRD diffraction.And based on the thermodynamic calculation results of FactSage7.2,the measures of pelletizing and pellet roasting had been carried out to explore the influence of different dephosphorization agents SiO₂ and CaCl₂ on the gasification and dephosphorization of high-phosphorous iron ores.The results showed that the phosphorus in high-phosphorous iron ores was in the form of Ca₅（PO₄）₃.After adding dephosphorization agent,the reaction temperature of gasification and dephosphorization began to decrease to 815 ℃.Under the experimental conditions of 1 250 ℃ and 5% carbon,0.8% SiO₂ and 1.6% CaCl₂ were added as the mixed dephosphorization agent,the optimum gasification dephosphorization performance had been achieved withdephosphorization rate of 22.1%.