The use of blast furnace slag and derived materials in the vitrification of electric arc furnace dust

Abstract

The electric arc furnace (EAF) dust was added to blast furnace granulated slag or a gel produced by dissolving slag in HNO3/EtOH followed by alkaline hydrolysis and gelification, and then it was vitrified. The proportion of EAF dust used was between 5 and 30 wt pct. The physicochemical properties of the glasses produced were studied by the X-ray powder diffraction technique, differential thermal analysis, and transmission electron microscopy (TEM). Thermal properties (dilatometric softening point, glass transition temperature, and thermal expansion coefficient) were determined. Finally, analyses were performed on leachability and ecotoxicity. The results suggest that the use of either slag or slag-derived gel produces a borosilicate glass with thermal properties similar to those of conventional soda-lime-silicate glass.