Steel Slag Asphalt: Preventing the Waste of a High Quality Resource

With this in mind, the steel industry within Europe now consider iron and steel slag to be products and not waste and as such have registered the materials under Reach (Registration, Evaluation Authorization and Restriction of Chemicals). Steel slag is formed by the addition of lime to the molten metal in order to remove impurities and to control the quality of the steel. The resultant slag is a complex mineral formed from oxides of calcium, aluminum, silicon and magnesium along with various other trace elements. Once cooled, the slag forms a crystalline rock that can be used as a replacement for natural aggregate in a variety of construction products, including Asphalt.