REWAS 2019 pp 215-220 | Cite as

Alkali Elution of Various Mineralogical Phases in Steelmaking Slag

  • Zuoqiao ZhuEmail author
  • Xu Gao
  • Shigeru Ueda
  • Shin-ya Kitamura
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


To suppress alkaline elution from steelmaking slag, the dissolution behaviors of mineralogical phases in slag need to be studied. In this paper, primary crystal phases (CaO·SiO2, CaO·SiO2·FeO, and CaO·SiO2·2MgO) of CaO–SiO2–FeOx and CaO–SiO2–MgO systems were synthesized, and their dissolution behaviors and the change in pH were investigated. The results showed that CaO·SiO2 caused the increase in pH by the dissolution of alkali. Therefore, the alkali elution from steelmaking slag is caused by not only free CaO and 2CaO·SiO2 but also CaO·SiO2. Then, slags corresponding to actual steelmaking composition in the system CaO–SiO2–FeOx and CaO–SiO2–MgO systems were synthesized and their dissolution behaviors were observed. The result showed that the pH values after the dissolution of every slag were lower than that of CaCO3, even though water soluble phases were contained in slag. Therefore, alkali elution from slag containing soluble phases can be suppressed when the mass fractions of these phases in slag are low enough.


Steelmaking slag Mineralogical phase Alkaline elution Primary crystal phase pH 


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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Zuoqiao Zhu
    • 1
    Email author
  • Xu Gao
    • 2
  • Shigeru Ueda
    • 2
  • Shin-ya Kitamura
    • 2
  1. 1.Graduate School of EngineeringTohoku UniversitySendaiJapan
  2. 2.Institute of Multidisciplinary Research for Advanced Materials, Tohoku UniversitySendaiJapan

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