A recent study from Heriot-Watt University has presented a potentially transformative approach for the steel industry. It suggests that switching to carbon negative processes could make low-grade iron ore commercially viable. This comes at a time when global demand for steel continues to rise, contributing to 5-8% of global carbon dioxide emissions.
The study, published in the Journal of Cleaner Production, suggests that integrating carbon dioxide removal technologies into steel production could significantly change the market dynamics for iron ore. High-grade iron ore, traditionally favoured for its lower energy and material requirements, could soon face competition from low-grade iron ore thanks to advances in emissions reduction technologies.
Paths to commercial viability
Professor Phil Renforth, leader of the research team, sees promising new investment opportunities: “In the UK, around 180 million tonnes of slag by-products are generated during steel production. If industry were to use this material to capture atmospheric carbon dioxide, for example by combining direct air capture with a mineral reaction system, it could remove up to one gigaton of carbon dioxide per year by 2050.”
Renforth’s study highlights the need for strong incentives to offset the expected higher costs associated with decarbonising steel production. The research opens a path to economic viability that can revitalise local industries and encourage industrial growth in the context of climate change mitigation.
“We developed a bespoke techno-economic model simulating scenarios in which steel production is enhanced by measures to combat climate change. We focused on measures such as direct reduced iron, biomass-based reductants and carbon capture and storage as these have been identified by the International Energy Agency as the most likely net-zero pathways. Our model shows that by integrating advanced emission reduction technologies and using lower-grade iron ore, we can create a sustainable, economically viable path to a carbon-negative steel industry.”
More information: P. Renforth et al, Carbon dioxide removal could result in the use of lower-grade iron ore in a decarbonized net-negative emission steel industry, Journal of Cleaner Production (2024). DOI: 10.1016/j.jclepro.2024.142987
