Method for assessing physical-chemical interaction in the metal-slag system as a cooperative ion-exchange process in steel refining

Abstract

Dephosphorisation and desulphurisation are the most important stages of high-quality steel production, characterized by complex physical and chemical processes of interaction in the metal-slag system. The article is devoted to studying the results and evaluating the efficiency of steel refining processes at different stages of its refinement in modern Ukrainian conditions. The aim of the work is to develop a methodology for assessing the physical and chemical interaction in the metal-slag system during steel refining from the perspective of the concept of a cooperative ion exchange process using the parameters of interatomic interaction in melts. As a result of studying the regularities of sulphur and phosphorus distribution depending on the chemical composition of different steel grades from two plants and their corresponding slags, a methodology has been developed that includes the reasonable use of parameters of interatomic interaction in melts as criteria for assessing the degree of completion of ion exchange processes during steel refining. Along with the use of integral physical and chemical parameters of the chemical and charge state of metal and slag melts (chemical equivalent of metal composition ZY(e) and slag Δe(e), effective charge of element Ze(e)), the paper shows the key role of the influence of the "recharge" parameter of the element ΔZе on the process of interfacial distribution of sulfur and phosphorus. This parameter has also shown its efficiency as a criterion for assessing the deviation of the metal-slag system from equilibrium at different stages of steelmaking and finishing at the ladle furnace unit (LFU). The proposed approach makes it possible to assess the level of completion of steel refining processes in order to develop effective technological solutions. In addition, it lays the foundation for solving specific applied problems at a new level, allowing optimizing existing technologies and developing new methods and reagents for producing steels with reduced sulphur and phosphorus content.