Gasification Removal Behaviour of Phosphorus Compounds from High‐Phosphorous Iron Ore

Abstract

The gasification removal behaviour of phosphorus from high‐phosphorus iron ore is theoretically and experimentally studied in the temperature range of 400–900 °C under H2 reducing and N2 atmospheres. In the first step, thermodynamic analysis is conducted to reveal the gasification and reaction behaviours of common phosphorus compounds, namely P4O10, FePO4, AlPO4, Ca2P2O7, and Ca3(PO4)2. The results indicate that P4O10, FePO4, and AlPO4 under H2 reducing atmosphere and P4O10 under a N2 atmosphere can be removed by gasification, and the influence of the interaction between the vaporized gases and iron ore should be investigated. Therefore, dephosphorization experiments are performed on simulated iron ores containing P4O10, FePO4, or AlPO4. For the sample containing P4O10, ferric phosphates and iron phosphides are formed under the N2 and H2 reducing atmospheres, respectively, and their formation rates decreases with decreasing temperature, becoming almost stagnant at 400 °C. Moreover, it is confirmed that FePO4 and AlPO4 cannot be removed even when pure H2 is introduced.