Steel desulfurization on RH degasser : physical and mathematical modeling.
No Thumbnail Available
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Due to the high-quality steel demand, especially for ultra-low Sulfur steel, RH
desulfurization has been practiced. Based on this, mathematical and physical modeling
have been applied to study steel desulfurization by reagent addition in the RH degasser
vacuum chamber. The main result of cold modeling, using water and oil emulating
steel and slag, respectively, was to assess the influence of density difference between the
continuous and disperse phases on oil droplet behavior. It is shown that its flow tends
to be more restricted near the down snorkel when the density difference increases.
Moreover, these results provide the basis for CFD modeling validation, which enabled
the determination of slag drop residence time inside steel on RH and the average value
of the rate of dissipation of turbulent kinetic energy inside the RH ladle. These two pa-
rameters were used to develop a kinetic model, which reaches a good agreement with
industrial trial results available in literature. The optimum desulfurization degree of
31.44% was achieved for a gas flow rate of 90 Nm3
/h, according to the kinetic model.
This value can be useful in some steel grade production, where the required S content is
less than 10 ppm. Even in common steel grade production, if some punctual chemical
adjustment is necessary, this technique is also useful. The main kinetic parameter for
steel desulfurization is the steel circulation rate. For best results, it should be reduced
in the desulfurization stage, and after that, the normal operation can be resumed, so
that the production cycle is not affected.
Description
Keywords
Modeling of steelmaking
Citation
SILVA, A. M. B. et al. Steel desulfurization on RH degasser : physical and mathematical modeling. REM - International Engineering Journal, Ouro Preto, v. 75, p. 27-35, jan./mar. 2022. Disponível em: <https://www.scielo.br/j/remi/a/wJ9TRHXvpWNWSdRhnRpjnSd/>. Acesso em: 29 abr. 2022.