Tecnologia em Metalurgia, Materiais e Mineração (Mar 2014)

MICROSTRUCTURAL STUDY OF THE LD CONVERTER SLAG AND ITS RELATIONSHIP TO THE DEPHOSPHORISATION PROCESS

  • Hugo Filipe Parreiras Gonçalves,
  • Carlos André Ruy Carneiro,
  • Túlio Carvalho da Silva Araújo

DOI
https://doi.org/10.4322/tmm.2014.006
Journal volume & issue
Vol. 11, no. 1
pp. 41 – 49

Abstract

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The LD converter slag plays an important role in the refining process, mainly in relationship to phosphorus removal. Much is known about the physicochemical characteristics of the slag and its relationship to the process efficiency; however few employ the microstructural aspect for such analysis. In this sense, the aim of this work was to analyze the slag microstructure formed at Usiminas converters and to understand important points relationed to dephosphorisation reaction, to act efficiently in the industrial process improvement. It was verified that dephosphorisation reaction does not occur in slag solid phases. According to this observation, the amount of fluxes added to the converter was reviewed, reaching a considerable reduction in the free CaO content of the slags. It was also observed a drop of approximately 10% in lime consumption at the converters, without influence in the mean phosphorus content at the end of oxygen blown.

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