Manufacturing iron and steel is an extremely energy-intensive process, and the industry is one of the highest greenhouse gas-emitting sectors.
Luca Mastropasqua, an assistant professor of mechanical engineering at the University of Wisconsin-Madison, is hoping to upend those emissions. With a $10 million grant from the U.S. Department of Energy’s Hydrogen and Fuel Cell Technologies Office, he’s pioneering technology for using clean hydrogen to decarbonize steel production.
Mastropasqua and his collaborators will implement their technology at the Cleveland Cliffs steel plant in Toledo, Ohio, to demonstrate the viability of their approach. “This project is an exciting opportunity to show this technology not just in the lab but in a real steel plant, which will be impactful for advancing decarbonization efforts in a hard-to-decarbonize sector,” Mastropasqua says.
Steel manufacturing involves taking mined iron ore and using a reaction to reduce it into metallic iron. Currently, steelmakers use natural gas or coal to perform this “direct reduction” process, which produces carbon dioxide as a byproduct.
As an alternative to the natural gas or coal, Mastropasqua will use renewable hydrogen for the direct reduction process. Its only byproduct? Water.
To produce the hydrogen, the team will use a device called a solid oxide electrolyzer cell which uses electricity generated from renewable sources such as wind and solar in a chemical process that breaks water into oxygen and hydrogen.
The solid oxide electrolyzer cell works at high temperatures, so the research team will integrate it with the Ohio steel plant’s shaft furnace, harnessing waste heat from the flue gas for hydrogen production.
“Our approach requires high temperatures, so we’re designing our system to exploit the waste heat from the plant, which will crucially allow us to reduce the electricity consumption of the electrolyzer,” Mastropasqua says. “This is very important because steel plants are enormous. We would need hundreds of megawatts of electricity from solar and wind to produce the amount of clean hydrogen needed to decarbonize just one plant.”
The team aims to install a 250-kilowatt solid oxide electrolyzer cell at the Cleveland Cliffs steel plant, which will be a small-scale proof of concept that is the first step to decarbonizing this plant and others. “The hope is that successful results from this project will pave the way for scaling up the technology so that it can make an impact on industrial carbon emissions,” Mastropasqua says.
Partners on the project include the University of California Irvine, Laboratoria Energia Ambiente Piacenza, FuelCell Energy Inc, Politecnico di Milano, the Electric Power Research Institute, Cleveland Cliffs, and SoCalGas.
Featured image caption: Assistant Professor Luca Mastropasqua in his HERD lab with a high-temperature electrolysis testing station. Credit: Caitlin Scott.