Utilization of metallurgical wastes as raw materials for manufacturing alkali-activated cements

The production of nonferrous metals, including aluminium, copper, manganese, zinc, lead, nickel, and tin, is forecasted to increase in the mid-21st century, and consequently, the amount of slags derived from their processing will significantly rise. Nonferrous metal slags are industrial waste streams produced in large volumes, whose disposal poses environmental hazards due to potential release of toxic elements. New technologies to enable their sustainable management are urgently needed, and alkali-activation technology offers a route to transform nonferrous slags into value-added cementitious products for construction. This chapter provides an overview of recent advances in the understanding of relationships between slag composition and hardened cement properties, as well as their long-term safety and durability. Beyond purely material aspects, this chapter puts these developments into context of the circular economy and discusses the opportunities and barriers for greater adoption of alkali-activation technology to valorize nonferrous slags.