Functions of Mg and Mg-CaO mixtures in hot metal desulfurization
2014 (English)In: Steel Research International, ISSN 1611-3683, Vol. 85, no 1, 76-88 p.Article in journal (Refereed) Published
The mechanisms of hot metal desulfurization using Mg and Mg-CaO mixtures were studied in a newly designed set-up. It was found that most of the added Mg quickly escaped in 2 s. MgS was not formed by homogeneous nucleation but by its formation on the MgO particles originated from oxide shell of the Mg particles. When tiny CaO particles were added together with Mg, the particles efficiently transformed to CaS. It was found that Mg-gas helped the distribution of the CaO particles in the hot metal and improved the kinetic condition. Most of the CaO particles smaller than 10 μm were completely transformed to CaS whereas CaO particles >10 μm still had CaO in the center after 20 s. The CaO particles as nuclei were also found to help Mg gas in forming MgS. The ratio of CaO and Mg added was found to have strong impact on the kinetic conditions of desulfurization. This ratio would need further study in any reactor of interest, as the kinetic conditions would differ considerably. The optimized ratio is expected to be a function of the size and geometry of the reactor, the position and the depth of the addition, the manner of addition and more. The hot metal desulfurization mechanisms using Mg and Mg-CaO mixtures were studied. Most added Mg quickly escaped in 2 s. MgS was not formed by homogeneous nucleation but by formation on oxide particles. When tiny CaO particles were added together with Mg, Mg-gas helped distribution of CaO particles in hot metal and improved kinetics. Most CaO particles sized <10 μm were completely transformed to CaS whereas CaO particles >10 μm still had CaO in the center after 20 s.
Place, publisher, year, edition, pages
2014. Vol. 85, no 1, 76-88 p.
CaO, hot metal desulfurization, Mg, reaction mechanisms, Homogeneous nucleation, Hot metal, Kinetic conditions, Oxide particles, Oxide shell, Reaction mechanism, Desulfurization, Kinetics, Magnesium, Mixtures, Nucleation, Metals
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-143068DOI: 10.1002/srin.201300071ISI: 000334354000010ScopusID: 2-s2.0-84892153729OAI: oai:DiVA.org:kth-143068DiVA: diva2:705581
QC 201403172014-03-172014-03-172014-06-13Bibliographically approved