Sustainable metal production and steel recycling

Researchers: Sharun Hedge and Ida Kero

The doctoral studies in this project focuses on the sorting and reintroduction of end-of-life steel scrap into the steel value chain. The objective is to improve sorting and characterization of steel scrap so that every steel class can be recycled as itself (alloy-to-alloy recycling).

Steel scrap is not a uniform material but a very diverse group of materials with widely different constituents and properties. Innovations in recycling may for example come from improved dismantling of old products, information sharing across value networks to enable optimization, as well as sorting and characterization of scrap so that every steel class can be recycled as itself (alloy-to-alloy recycling).

Sustainability aspects

Scrap-based steel production is recognized by the world steel association as one of few strategies compatible with a (near-) zero-emission pathway. It relies on mature technologies with much lower capital investment costs than other methods with comparable potential for climate mitigation. Importantly, scrap can easily be combined with other fossil-free iron sources (e.g. from hydrogen-based direct reduction) in the same processes.

Other societal and financial motivations for increasing recycling, avoiding downcycling and reducing the reliance on iron ores is for example to improved societal resilience, reduce supply chain risks and increase the ability to retain and make use of the critical and strategic raw materials which are often included in steel as alloying elements. Scrap-based steel production has much lower industrial greenhouse gas emissions, water and energy consumption as well as land area use than the ore-based process which dominates today. This project directly supports the UN SDG’s 8, 9, 11, 12, and 15.