Jose Adilson de Castro

Abstract:

The shaft furnace process is widely used to produce DRI from pellets and lump ore. One of the largest shortcomings of the process is the need for a reforming gas station for producing reducing gas. This study proposes the enhancement of the efficiency of the process using self-reducing burden with poor reducing gas. A numerical model based on transport equations of momentum, energy and chemical species for gas and solid phases is proposed to simulate the inner phenomena in the direct reduction of the shaft furnace process for producing direct reducing iron (DRI). The model is verified using industrial data of productivity, raw materials and final composition of the DRI product. The model is used to evaluate operational practices using new raw materials and composition of reducing gas in the process. Five cases were considered which correspond to available raw materials and operational conditions on the process. The effects on the gas and solid inner temperature, pressure and phase compositions distributions are quantified. The simulation results indicated that good agreement for overall parameters of the process could be achieved. Afterwards, detailed features of the inner conditions of the process are predicted.

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