The power of steelmaking-harnessing high-temperature reactions to transform waste into raw material resources

Abstract

Iron- and steelmaking processes present a largely untapped opportunity to transform some of the world's most problematic waste streams into raw materials for production. This opportunity lies in their high-temperature environments, which offer sustainable pathways for utilizing chemical reactions to repurpose waste materials as resources, such as reducing iron oxide to iron and dissolving the carbon in waste materials into metal. High- Temperature environments can be leveraged to revolutionize the role steelmakers play in globally significant, large-scale recycling, without making fundamental changes to manufacturing processes. This presentation describes the broad opportunities available to iron- and steelmakers to utilize waste streams - ranging from polymeric materials to agricultural wastes - as raw materials. The potential to implement such novel recycling solutions are not generally available to many other materials industries because they operate at relatively lower temperatures, which may not be suitable for triggering useful chemical transformations. Recycling waste polymeric materials in steelmaking is one solution for end-of-life products, which currently impose a serious burden on overstretched landfills, as is the case with some plastics. Specifically, this lecture presents fundamental understanding of different plastic wastes - melamine, high-density polyethylene, polycarbonate and Bakelite, as well as agricultural waste and tires - and their transformations and chemical reactions at high temperatures. Plant results from EAF steelmaking in Sydney, Australia, where recycling waste is now standard practice, will also be included