THERMODYNAMIC ANALYSIS OF AN ELECTRIC-ARC FURNACE

A thermodynamic analysis was performed on a 44-tonne capacity electric arc furnace. The results obtained showed that this process of billet steel manufacture from scrap iron has a specific energy consumption of 520 kWh/tonne of billet steel. First- and second-law efficiencies, based on electric energy input, were 84.7 and 58.6%, respectively. Modified first- and second-law efficiencies which considered the chemical energy from exothermic reactions as inherent energy input were 54.9 and 36.3%, respectively. Several areas in the production process were examined for the purpose of energy conservation and production cost reduction. The scrap charging and preheating sub-processes offered potential for energy saving for the steel mill.