Energy consumption during HCFeCr production at Ferbasa

Abstract

Improved understanding of energy distribution in the furnace and of the effect of different parameters on specific energy consumption is important when means to reduce energy consumption are evaluated. A staged energy and material balance has been calculated for HCFeCr production at Ferbasa based on the charge mixture in February 2011. In the main example, the calculated total energy consumption per ton of alloy is 3585 kWh/ton of alloy. Losses in power supply and heat losses from furnace shell are not included. This is assumed to be within the normal range for HCFeCr production. 73 % of the energy is consumed at temperatures between 1200 OC and 1700 OC, in the coke bed zone in the furnace. Total consumption and consumption in the different zones is similar to values calculated earlier for Elkem Rana. The effect on energy consumption of different parameters has been calculated based on the results from this balance. Here a theoretical charge mixture based on a single Brazilian chromite ore, Jacurici, was used. The effect of variations in temperature and composition of both off gas and slag were calculated as well as the effect of varying Sicontent in the produced alloy. Drying and preheating are possible methods to reduce energy consumption and effect on energy consumption of moisture and raw material temperature have was thus been calculated for various cases. Energy distribution in the furnace is described by a staged energy balance.