A Kinetic Model to Simulate the Reaction Between Slag and Matte for the Production of Ferromanganese Alloy from Steelmaking Slag

Abstract

Manganese is used as a key alloying element in various advanced steel products to improve their mechanical properties. The authors have proposed an innovative process to recycle Mn from steelmaking slag. In this process, steelmaking slag is first sulfurized to separate P and Mn, and then the matte is oxidized to increase the Mn/Fe ratio. The equilibrium distribution ratio of Mn, Fe, and Ca between slag and matte has been already clarified. To design an industrial process, a kinetic model to simulate the various reactions that occur simultaneously between the matte and slag was developed by applying the coupled reaction model. In this kinetic model, the mass transfer was calculated by the double film theory by assuming the equilibrium at the interface. The calculation results agreed well with the concentration changes of each element in the matte and slag obtained by experiments. The optimum conditions for the treatment were discussed using this model, and multi-step sulfurization and oxidation processes were proposed.

A Kinetic Model of Mass Transfer and Chemical Reactions at a Steel/Slag Interface under Effect of Interfacial Tensions

“…Based on the above proposed mechanism, Ni et al 7) developed a kinetic model to describe this dynamic change of the interfacial tension, where the silica decomposition at the interface, the oxygen adsorption and desorption at the interface and the mass transfer in the steel and slag phase were considered. This model is different from some previously reported kinetic models [8][9][10] since the effects of the interfacial tension on both interfacial reactions and the transport of some interface active elements were considered. Furthermore, the current model is not based on the mass flux balance assumption at the interface which commonly has been used in previous kinetic models.…”

“…Furthermore, the current model is not based on the mass flux balance assumption at the interface which commonly has been used in previous kinetic models. [8][9][10] In this paper, the new kinetic model was further developed based on the previous model developed by Ni et al 7) to include the aluminum reaction with oxygen in the interfacial region and the dissolution and transfer of the formed alumina to the slag phase. This aims to describe the dynamic behavior of the interfacial tension in a more realistic way, since reductive elements commonly exist in some steels.…”

A Kinetic Model on Oxygen Transfer at a Steel/Slag Interface under Effect of Interfacial Tension

“…In the past, some kinetic models [11][12][13] have been proposed to describe the mass transfer from molten slag to liquid steel. However, the effects of the interfacial tension on both interfacial reactions and the transport of some interface active elements have been neglected.…”

Mathematical Modelling Study of Dynamic Composition Change of Steel and Mold Flux in Continuous Casting of Steel

“…12,13) In addition, some kinetic models were also developed to describe the steel/slag reaction during metal refining process. [14][15][16] This kind of kinetic model is based on the groundbreaking kinetic model-coupled reaction model, which was developed by Robertson et al 14) in 1984 and now are widely used to predict the process kinetics in metallurgical field. These models are based on the assumption that the mass flux balance and the reaction equilibrium exist at the interface.…”

“…This makes the kinetic model special with respect to describing the kinetics of the steel/flux system close to the reality where the interfacial tension exists, compared to some previously reported kinetic models. [12][13][14][15][16] In this paper, a new kinetic model was further developed based on the previous model developed by Ni et al 19,20) to include the multicomponent reactions with oxygen in the interfacial region in a continuous casting mold. This new model considers the following mechanisms: i) silica decomposition and oxygen adsorption at the interface, ii) reaction between oxygen and reductive elements in steel at the interface, iii) oxygen desorption from the interface to the steel bulk, iv) silica mass transfer from the molten flux to the interface, v) dissolution of the formed interfacial reaction products into the flux and their transfer in the flux.…”