Parameters Affecting Energy Consumption for Producing High Carbon Ferromanganese in a Closed Submerged Arc Furnace

The power consumption is considered to be the most important factor affecting the production cost of ferromanganese alloy. Different parameters affecting the energy consumption for industrial production of high carbon ferromanganese HCFeMn were investigated in a closed submerged arc furnace. The analysis of industrial data revealed that the most energy-consumed factors were the direct reduction by solid carbon, Boudouard reaction, metal and slag formation, and decomposition of fluxing materials (limestone and dolomite). To reduce the energy consumption and minimize the energy losses in the production process of HCFeMn, it was recommended to use Mn blend with minimum Mn to Fe ratio of 6 and lower SiO2 content or higher basicity. The added coke must be adjusted according to the material balance to prevent the over-coke and to minimize the highly endothermic “Boudouard reaction”. In addition, it was recommended to work at basic slags with the ratio of (CaO+MgO) to SiO2 equal to 1.0–1.2 instead of much higher slag basicity. Furthermore, the mass losses had to be minimized through adjusting the handling and charging process and to take care of all metal produced.