Estimation of Energy Consumption in COREX Process Using a Modified Rist Operating Diagram

Fuel consumption in the COREX-3000 process run in Baosteel is currently higher than the design index. Therefore, mass and heat balance equations for the COREX process were established using the basic principles included in the Rist operating diagram for blast furnace (BF) as a reference. Thermodynamic calculations were then used to modify the Rist operating diagram so that it was suitable for the COREX process. The modified Rist operating diagram was then applied for the evaluation of metallization rate (MR) and fuel structure to reduce the energy consumption in the COREX process. The modified Rist operating diagram for the shaft furnace (SF) provided a nearly ideal value for the restriction point W when the metallization rate was increased, while the point P on the operating line for the melter gasifier (MG) moved upward due to reduction in the heat required in hearth. The feasibility of reducing the energy consumption during the COREX process by changing the fuel structure was also demonstrated.