Papers by Keyword: Ladle Metallurgy

Abstract: In this work a kinetic model which describes the main refining reactions in a ladle furnace is depicted. The main difference between this work and other models previously reported relies on a formal quantification of the multi-component diffusion kinetics expressed as an analytical solution. Results from this model reproduce/predict adequately the chemical steps involved in an integrated steel shop.

Abstract: The interfacial reactions between a solidified Fe shell and Ti were investigated within the framework of steel alloying. Ti cylinders were immersed into liquid Fe for various durations and subsequently water-quenched. An Fe shell solidifies around the Ti. At the interface between Fe and Ti a reaction zone is formed. Initially it consists of a liquid eutectic layer, though in later stages all stable phases at elevated temperature can be found in the quenched microstructure. The larger part of this reaction zone is fluid at high temperature and both Ti and Fe dissolve into it. Moreover, intermetallic compound formation and mixing of Fe and Ti generate extra heat, shortening the time required for shell melt-back. The reaction zone reaches thicknesses up to 40 % of the initial sample’s radius and when the shell has completely remolten, a discontinuity in the thickness-time profile is expected. The exact morphology of the reaction zone at high temperature remains to be determined: presence of a solid layer of Fe2Ti may impede mixing in the initial stages.

Abstract: It is generally well known that a steelmaking ladle operation plays an important role in the production of clean steel. A turbulent mixing of melt with Ar gas bubbling from the ladle bottom can homogenize a melt temperature and can control precisely chemical compositions of steel. In order to figure out these phenomena, a quantitative analysis of fluid flow behavior of gas and melt during a ladle operation is required and special concerns should be focused on effects of operating parameters on the perfect mixing time of melt. In this study, as a basic approach, effects of operating parameters such as a melt depth (aspect ratio) and a nozzle type (one-hole or porous plug) on the mixing behavior in ladle operation are investigated. Water model experiments are carried out to simulate these melt behaviors in steelmaking ladle. As a result, it was found that there exist an optimized melt depth and a nozzle type at a given gas flow rate, which affect significantly on the mixing behavior of melt.