Abstract:
Increasing demand for low sulfur steels has led some steelmakers to study ways to optimize desulphurisation treatment in steel to reduce the consumption of desulphurizing agents, sulfur content and treatment time in secondary refining. In this paper, the evolution of sulfur during the desulphurisation of steel in the ladle furnace was analyzed in 30 experimental heats using a micropulverized mixture containing lime and fluorite. After evaluating the results and the thermodynamic and kinetic conditions, equations were developed to predict the mixture weight to be injected to obtain the target sulfur content. The optimization of the process resulted in the reduction of 1.1 kg/t micropulverized mixture, 0.22 kg/t of aluminum, 562 kW of energy, 5,4 kg electrode/heat and 2 minutes of treatment.