Devitrification of granulated blast furnace slag and slag derived glass powders

Abstract

Vitrification has long been considered as a means of stabilizing hazardous industrial wastes prior to their direct disposal on landfills. In other cases, vitrifica- tion leads to marketable end-products. For instance, vitrification of electric arc furnace flue dust has recently become operative at industrial scale [1, 2]. In this process, the flue dust is mixed with a number of glass-forming materials, additives to adjust the composition and possibly other wastes such as blast furnace slag, and subsequently melted to form glass. A different approach, consisting in previously modi- fying the slag to yield glass-precursory powders, is currently under study by the present authors. In particular, it has been shown [3] that modification of the slag via sol-gel techniques permits one to obtain, in a relatively easy manner, a wide variety of glass precursors with controlled composition.