Growth and aggregation control of spinel by shear-force-based melting modification of stainless steel slag

Abstract

To improve the efficiency of melting modification for stainless steel (SS) slag, a shear force was introduced in this work and its effects on the spinel and silicate melt were experimentally investigated. The results indicated that the use of shear force changed the nucleation and growth behaviors of spinel and that the effects of shear force varied with its intensity. The aggregation behavior of spinel under different shear-force conditions was studied, revealing that large spinel clusters could be formed when the stirring speed was controlled. However, no notable change in the melt structure of the silicate was detected in this study. The optimal stirring speed for the melting modification treatment was 50 r·min⁻¹, which substantially promoted spinel growth and aggregation, resulting in modified SS slag with excellent chromium sequestration capability.

Keywords

stainless steel slag / spinel / crystal growth / melting modification / shear force / chromium sequestration

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