Making Steel with Electricity
The Siderwin research project tested a new method of steelmaking that uses direct electrolysis of iron oxide in a pilot plant in France. The steelmaker ArcelorMittal now announced that it wants to commercialize the technology.
The production of steel is a significant contributor to climate change. Direct emissions from steelmaking are around 7 percent of worldwide carbon dioxide emissions.
Iron ore, the raw material used for steelmaking, contains iron oxide, which means the iron atoms are bound to oxygen atoms. To break this bond, the standard steelmaking process in blast furnaces uses coke made from cooking coal. This process creates large amounts of carbon dioxide emissions that cannot be avoided with the existing technology.
An alternative to blast furnaces is using hydrogen in a process called direct reduction. This is often considered the most promising technology for green steel production, and many steel companies have announced investments in it. I have covered this in an earlier newsletter.
The project Siderwin has tested a different approach in a pilot plant in Maizières-lès-Metz, where the steel company ArcelorMittal operates a research facility. Siderwin uses direct electrolysis of iron oxide in a process called electrowinning. In other words: Pure electricity is used to split iron oxide into its elements. In a recent Webinar, the project presented some of its results – and ArcelorMittal announced that it wants to scale up the technology.
