Influence of MgO Additive on Fluidized Bed Reduction of Iron Ore Fines under Simulate COREX Reducing Gas

Influence of mixing MgO additive on fluidized bed reduction of iron ore fines using simulate COREX reducing gas was investigated. Experiments were conducted at 1073 K in a visualization fluidized bed. Mixing MgO additive was carried out using powder method and solution method. It was found that mixing MgO into ore fines using solution method could increase fluidization time from 12 to 80 minutes, and improve the metallization ratio from 22% to 81%. Reason was that coating MgO could effectively insulate the contact of metallic iron on particles, which provided the reaction time for carbon deposition and the production of Fe3C with low stickiness. Therefore, the decrease of metallic iron on particle surface led to the decrease of particle stickiness in fluidized bed reduction