Kuznetsov D. The development of the silicon distribution theory between metal and slag and improving production technology of low-silicon steels in ladle-furnace unit

The subject of research - process of metal refining during its treatment in a ladle furnace. The goal of research - technological development of low-siliceous steel secondary refining in a ladle furnace, which provides regimented silicon content by means of its removing from the metal in the ladles, based on development of theoretical model concerning the process mechanism of silicon recovery and oxidation within the system metal-slag. We used the theoretical and experimental approaches, which are based on fundamentals of metallurgical and mass transfer processes theory. Laboratory studies of redox reactions between metal and slag during the ladle treatment were performed in the laboratory kryptol furnace. Industrial research on the effectiveness of silicon removal in the steel ladle technology was carried out in the ladle furnace of PJSC Alchevsk Metallurgical Plant, using design method. Modern control members of secondary refining temperature conditions, scanning X-ray fluorescence spectrometer for chemical analysis of slag, a vacuum optical emission spectrometer for metal chemical analysis and electronic weighing equipment were used through studies. The PC was used for mathematical modeling of physical, chemical and technological parameters of secondary refining, as well as for statistical data processing. The mechanism of desiliconization of aluminum-killed low-carbon and low-siliceous steel in the process of its treatment with reducing slag in the ladle furnace as a result of sylicothermical magnesium recovery reaction was discovered for the first time. There was developed the idea of the pair reactions effect on the kinetics of silicon recovery during the final period of producing of aluminum-killed low-carbon and low-siliceous steel in a ladle furnace. For the first time there was discovered the the mechanism regulating aluminum and carbon content in aluminum-killed low-carbon and low-siliceous steel in the process of its treatment in the ladle furnace while desiliconization by feeding magnesium oxide to the combustion region of the electric arcs. The proportion of silicon recovered from silica slag during the process of producing of aluminum-killed low-carbon and low-siliceous steel in a ladle furnace was determined. The technology implemented at PJSC Alchevsk Metallurgical Plant, confirmed economic impact was 313092 UAH. Field of application - low-siliceous steel secondary refining in a ladle furnace.