Study on the Optimization of Fluidization Reduction Conditions of Brazilian Iron Ore Powder

The reduction behavior of Brazilian iron ore powder was studied in a pressurized visible fluidized bed.It was found out that the metallization rate was increased by increasing the pressure properly,and the fluidization state improved by adding carbon powder.In order to further optimize the effects of reduction time,reduction pressure,linear velocity of reduction gas,reduction temperature,carbon content and particle size on the reduction of Brazilian mineral powder,six factors and three levels orthogonal experiment method were used to test the bond ratio and metallization rate of Brazilian mineral powder samples after reduction.Experiments resultsindicated that different reduction conditions had different effects on the reduction of Brazilian mineral powder.Optimum reduction temperature of Brazilian ore powder by pure hydrogen was 923～1 023 K,the linear velocity of reduction gas was 0.6 m/s,the reduction time was 30～50 min,the reduction pressure was 0.25 MPa,the content of carbon powder was 2%～6%（accounting for the quality of ore powder） and the particle size of carbon powder was 4～7 μm.