Effects of Minor Elements to the Liquidus Temperatures of Blast Furnace Slags

Abstract

The effects of minor elements TiO₂, MnO, Na₂O, K₂O, CaS, and B₂O₃ to the liquidus temperatures of blast furnace slags were experimentally studied. The base blast furnace slag composition in SiO₂–Al₂O₃–CaO–MgO system is fixed at CaO/SiO₂=1.1, 16 wt% Al₂O₃ and 8 wt% MgO. The liquidus temperatures of the synthetic slags have been determined by high temperature equilibration, quenching and Electron Probe X-ray Microanalysis (EPMA) techniques. It was found that within the present investigated composition ranges, the additions of minor elements to the BF slags remain in melilite primary phase field. The minor element decrease the liquidus temperatures of the blast furnace slags in different extents and follows the tendency: B₂O₃ > CaS > Na₂O > K₂O > “TiO₂” > MnO. The present measurements were also compared with FactSage predictions.