Термодинамічний аналіз фізико-хімічних процесів в високотемпературній реакційній зоні рідкої сталеплавильної ванни. Частина 1. Системи залізо-кисень, залізо-кисеньвуглець

• Date: 2023
• Main Authors: Харченко, Олександр, Лічконенко, Наталія
• Format: Article
• Language: Ukrainian
• Published: Physico-technological Institute of Metals and Alloys 2023
• Subjects: високотемпературна реакційна зона; сталеплавильна ванна; продування киснем; кисневий конвертер; енергія Гіббса; хімічний потенціал; фазова діаграма
• Online Access: https://www.metalsandcasting.com/index.php/mcu/article/view/3
• Journal Title: Metal and Casting of Ukraine

The work is devoted to the analysis of physical and chemical processes in the high-temperature reaction zone (HRZ), which is formed in the autothermal steelmaking processes with oxygen blowing, such as converter production. The publication contains important theoretical and practical aspects of the research of HRZ in the context of development of new effective metallurgical technologies, as well as projecting and optimization steelmaking systems. Detailed thermodynamic analysis of HRZ has been conducted, and the parameters of liquid steel bath HRZ have been determined: temperature, multiplicity of slag and gas, chemical composition of metal, slag and gas phases. Calculations of parameters of HRZ were carried out using research software complex “Excalibur” based on the method of chemical potentials of Gibbs. It has been shown that by increasing the intensity of oxygen blowing it is impossible to reach arbitrary increase in temperature of HRZ, and therefore, temperature of the steel melting bath. The effect of the initial carbon content in metal and the total oxygen content on the HRZ parameters was investigated. It has been proved that the degree of combustion of the carbon linearly depends on the content of oxygen in the HRZ, and thus, on the intensity of blowing. Only near small values of carbon content there is exponential approach to zero level. It has been found that the intensive transition of iron into the gas phase begins in the carbonic HRZ after the burning of carbon from metal at the total oxygen content of more than 5 %. At the same time, there is a synchronous decrease in carbon content and an increase in the amount of iron in the gas. It is concluded that the carbon contained in the metal of HRZ is a catalyst for the transition of the iron into the gas phase and, accordingly, the irrevocable loss of iron in the steelmaking process. The results of the study allowed to build previously unknown fragments of equilibrium phase diagrams of the state of the high-temperature region of systems “iron-oxygen” and “iron-oxygen-carbon”.