Influence of slag basicity and temperature on Fe and Mn distribution between liquid Fe-Mn-Ca-O-S matte and molten slag

Sun Joong Kim, Jun Takekawa, Hiroyuki Shibata, Shin Ya Kitamura, Katsunori Yamaguchi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We have proposed a novel process for recycling Mn wasted in steelmaking slag via sulfurization to separate P from Mn. For clarifying the efficient recovery of Mn from steelmaking slag, the influences of slag basicity and temperature on the distributions of Mn and Fe between the Fe-Mn-Ca-O-S matte and FeO- MnO-MgO-P2O5-SiO2-CaO slag were investigated. The distributions of Fe and Mn between the matte and the slag increased with an increase in the slag basicity. Moreover, when log P S2 (PS2: partial pressure of S) was more than ?2, the Mn distribution increased to be more than 10 as the slag basicity increased beyond 1.7. Even though the effects of slag basicity and PS2 on the Mn content in the matte were small, the behavior of Mn in the matte was dependent on temperature. In order to understand the behavior of Mn and Fe in steelmaking slag and matte, the relationship between the activity coefficient ratio of MnS and FeS (λMnS/λ FeS) and the mole fraction ratio of MnS and FeS for the matte was investigated. To evaluate λMnS/λ FeS for the matte, the activity coefficient ratio of MnO and FeO (λMnO/λ FeO) was estimated using an empirical formula and the RS model, and the mole fractions of MnS and FeS in the matte were calculated on the basis of mass balance. The results revealed that the values of λ MnS/λ FeS for the Fe-Mn-S-O matte were about twice those for the Fe-Mn-Ca-S-O matte. Moreover, λMnS/λ FeS for the Fe-Mn-Ca-S-O matte decreased with an increase in temperature.

Original languageEnglish
Pages (from-to)1715-1724
Number of pages10
JournalISIJ International
Volume53
Issue number10
DOIs
Publication statusPublished - 2013 Nov 18
Externally publishedYes

Keywords

  • Activity coefficient
  • Iron sulfide
  • Manganese
  • Manganese sulfide
  • Matte
  • Phosphorus
  • Recycling
  • Slag basicity
  • Steelmaking slag
  • Sulfurization

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Influence of slag basicity and temperature on Fe and Mn distribution between liquid Fe-Mn-Ca-O-S matte and molten slag'. Together they form a unique fingerprint.

  • Cite this