Modelling of Defluidization of ZrO2/Fe Particles in High Temperature Gas Fluidization: Influence of Fe Contents

The contents of Fe on the surface of iron ore fines had a great influence on the fluidization behavior during high temperature fluidized bed reduction, which would cause defluidization when exceeding a critical value. In this paper, simplistically, ZrO2/Fe particles with different Fe contents on the surface were used as raw materials. Through modification of previous models, a quantitative relationship was established to predict the defluidization temperature of ZrO2/Fe particles with different Fe contents, and the calculation results corresponded well with the experimental data obtained from the defluidization test. The model in this paper firstly explained the dependence of defluidization behavior on the contents of Fe in high temperature gas fluidization, and it could well predict the metallization degree of commercial iron ore fines when defluidization occurred during fluidized bed reduction. Therefore, the model could be used as a reference to select suitable operating conditions for treating fine iron oxide particles in high temperature gas fluidization processes, such as direction reduction and chemical looping.