Using autoclave pulverization technology to evaluate the expansion potentiality of electric arc furnace oxidizing slag

Abstract

In this study, four different sources of electric arc furnace oxidizing slag (EOS) were selected. The relationship between the composition of EOS and its expansibility was analyzed, and an autoclave pulverization rate test technique was developed to evaluate the expansibility of EOS. When the MgO/(FeO+MnO) in EOS is < 1 and the content of f-CaO does not exceed 0.40%, this can be used as the threshold for the lack of expansibility of EOS. The agglomeration phenomenon of particles is the factor affecting the autoclave pulverization rate test. For EOS with a particle size of #30-#100, the most obvious agglomeration phenomenon was produced in the autoclave environment, and its pulverization rate was greatly reduced. When the particle size of EOS was increased to #8-#30, the agglomeration phenomenon improved. When the particle size was increased to #4-#8, no obvious agglomeration problem was found. Thus, taking #4-#8 as the sample size of the autoclave pulverization rate test, after 3 h in the environment of 2.0 ± 0.07 MPa (a corresponding temperature of 216 ± 2 ℃), the pulverization rate did not exceed 1.7%, and the EOS was judged to have no expansibility.

Keywords

• Electric arc furnace oxidizing slag
• Steel slag
• F-CaO
• F-MgO
• Expansion