KINETIC MODEL OF DESULPHURIZATION FOR PRODUCTION OF ULTRA LOW SULPHUR NON GRAIN ORIENTED SILICON STEEL BY INJECTION OF FLUX POWDER IN RH DEGASSER

• Main Author: ADE PATRIONA (NIM : 12507006), YELSI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/24771
• Institution: Institut Teknologi Bandung

Desulphurization process by powder injection during production of ultra low carbon and ultra low sulphur silicon steel (C < 30 ppm and S < 30 ppm) on RH <br /> <br /> <br /> <br /> plant, shall be performed after decarburisation and deoxidation. Determination of sulphur distribution ratio in the slag formed by injected powder (Ls) and sulphide <br /> <br /> <br /> <br /> capasity (Cs), which was introduced by Sosinsky and Sommerville, are applied to predict the final sulphur content in molten steel. While kinetic desulphurisation <br /> <br /> <br /> <br /> model on RH plant by powder injection has been developed by Wei. In this study, the kinetic desulphurization rate constant is determined using the kinetics equation <br /> <br /> <br /> <br /> introduced by Wei. Furthermore, Deo's model is used to calculate the sulphur content in molten steel as function of time with respect to equilibrium sulfur <br /> <br /> <br /> <br /> concentration. Simulation results have been verified with several plant trial data from industries. This study shows that the combination of Wei's and Deo's <br /> <br /> <br /> <br /> kinetic model can be used to predict the decrement of sulphur content in a RH degasser conducted by powder injection through a lance. Simulation results show <br /> <br /> <br /> <br /> that the optimum amount of injected powder is in the range of 3 - 6 kg/ton of steel. The total desulphurisation treatment time will be 21-27 minutes at oxygen content less than 5 ppm. Such desulphurization condition may reduce the sulphur content in the molten steel from 70 ppm to less than 10 ppm with depent on the <br /> <br /> <br /> <br /> amount of injected flux the efficiency of processis ranging from 67 to 89%.