Термодинамічний аналіз фізико-хімічних процесів у високотемпературній реакційній зоні рідкої сталеплавильної ванни. Частина 2. Видалення домішок

• Datum: 2023
• 1. Verfasser: Харченко, Олександр
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Physico-technological Institute of Metals and Alloys 2023
• Schlagworte: високотемпературна реакційна зона; сталеплавильна ванна; продування киснем; кисневий конвертер; домішки; енергія Гіббса; хімічний потенціал
• Online Zugang: https://www.metalsandcasting.com/index.php/mcu/article/view/39
• Назва журналу: Metal and Casting of Ukraine

Removal of impurities from the gas phase of a liquid steelmaking bath is an important process in which chemical elements are irretrievably removed from the space of the steelmaking unit. There is a need to study this process in detail when blowing a liquid iron-carbon melt with oxygen in order to effectively control the technological parameters of melting. The paper studies the behavior of iron and impurities of carbon, oxygen, silicon, manganese, aluminum, sulfur, phosphorus, calcium and magnesium in the gas phase of the high-temperature reaction zone (HTRZ) of a liquid steelmaking bath when it is blown with oxygen, taking into account the influence of all components of the thermodynamic system “metal-slag-gas”. It is shown that as the blowing intensity and bath temperature increase, the concentration of a number of impurities in the gas phase of the HTRZ passes through a maximum at a certain temperature, which depends on the blowing intensity, after which the intensive removal of given impurity from the steelmaking bath begins. In absolute units, as the temperature increases, the escape of given impurity into the gas phase does not decrease, and in the general case no maxima are observed. According to the temperature and the degree of removal into the gas phase, the studied impurities can be divided into three groups: a) carbon, which is almost completely removed at a relatively low total oxygen content in the HTRZ and temperatures up to 2000 °C; b) silicon, calcium, magnesium and phosphorus, which are almost completely removed into the gas phase in the temperature range of 2100...2800 °C; c) manganese, sulfur, iron and aluminum, which are partially removed at temperatures above 2600 °C. With an increase in the total oxygen content in the HTRZ above 15 %, the temperature increase sharply slows down, reaching the limit of 2900 °C at a total oxygen content of 20 %. In this case, iron intensively escapes into the gas phase along with impurities. In addition, a significant amount of slag is formed, consisting mainly of iron oxides. Therefore, blowing the steelmaking bath with oxygen at a rate of more than 5 m3/(t·min) is inappropriate, since it does not lead to a significant increase in the productivity of the steelmaking unit.