Characterization of Moroccan steel slag waste: The potential green resource for ceramic production

Abstract Steel slag is one of the most common waste products from the steel making industry. In this research, building bricks based on electric arc furnace (EAF) slag were examined. Five mixtures were prepared by mixing variable percentages of EAF from 5 to and 25% by weight with Messinian and Miocene clays from NE Morocco. The effects of the slag content on ceramic proprieties were investigated during drying and firing over temperature ranging between 700 and 1100 °C. Shrinkage of fired clay bricks decreases with increasing the amount of steel slag. The water absorption and porosity of the bricks decreased with increased firing temperature due to a reduction of the connectivity of the pores. The decrease of porosity is linked to the formation of glassy phases confirmed by XRD results. The presence of EAF slag contributes to the formation of new crystalline phases such as gehlenite, cristobalite, lazurite, leucite and mullite. The addition of 15, 20 and up to 25 wt% of slug does not induce any significant variations in their technological properties.