Review on the innovative uses of steel slag for waste minimization

Piles of steel slag, a solid waste generated from the iron and steel industry, could be seen due to no utility found for the past century. Steel slag has now gained much attention because of its new applications. The properties of slag greatly influence its use and thus had got varied applications. The chemical composition of steel slag varies as the mineral composition of raw material such as iron ore and limestone varies. This paper reviews the characteristics of steel slag and its usage. The paper reviews recent developments in well-known applications to the steel slag such as aggregate in bituminous mixes, cement ingredient, concrete aggregate, antiskid aggregate, and rail road ballast. This paper also reviews novel uses such as mechanomutable asphalt binders, building material, green artificial reefs, thermal insulator, catalyst and ceramic Ingredient. The review is also done on utilization of solid waste for waste management by the novel methods like landfill daily cover material, sand capping, carbon sequestration, water treatment and solid waste management. Review also shows recovery of pure calcium carbonate and heavy metals from slag, providing opportunity for revenue generation. Steel slag once traded as free to use by steel industries is now sold in the market at some price. Its utilization is of great economic significance as it also contributes to the reduction of solid waste.