Simulated shaft furnace assesses hydrogen as fuel for furnaces

Hydrogen’s utility as a reductant for steelmaking is the subject of a study by steel specialists who are using a simulated shaft furnace to help make the assessment.

Inside the shaft furnace. The team’s focus on hydrogen as a fuel for furnaces has enormous potential to cut carbon emissions
Inside the shaft furnace. The team’s focus on hydrogen as a fuel for furnaces has enormous potential to cut carbon emissions - Steel And Metals Institute, Swansea University

The team used laboratory simulations to get an accurate picture of how hydrogen and other materials behave in the extreme conditions of a furnace, as a first step towards piloting a new type of hydrogen-fuelled process.

The study was a collaboration with the Steel and Metals Institute, based at Swansea University, and the Materials Processing Institute, based in Middlesbrough working with global metals and mining companies. The project was funded by the BEIS Industrial Fuel Switching Programme.

Steel can be recycled infinitely with no loss of quality, but the process of manufacturing steel remains carbon-intensive with six per cent of global carbon emissions coming from the ironmaking process, and a single blast furnace producing five million tonnes of carbon annually.

At present, iron is reduced in the furnace using carbon monoxide from coke, which attracts oxygen from the iron ore. The result is that the iron ore becomes pure iron that is ready for steelmaking, but the extra atom of oxygen turns carbon monoxide into the greenhouse gas carbon dioxide.

If hydrogen could be used to reduce the iron it would significantly reduce carbon emissions from steelmaking.

The team examined how materials behaved in the hydrogen reduction process and to do this they used a reducibility rig, a unique technology based at Swansea University’s Steel and Metals Institute (SAMI) that simulates what happens to materials at very high temperatures in gas-laden environments.

In a statement, Dr Mike Dowd from SAMI said: “Switching to hydrogen as a reducing agent for steelmaking would slash carbon emissions.  Our work tested how this technology could work, before we start the next phase of this project.

“The reducibility rig in Swansea allows us to take a virtual look at the hydrogen reduction process could work on an industrial scale.  It means we get a full picture of how materials behave in extreme conditions.  We also compare hydrogen with carbon-heavy fuel sources.”

Dr Dowd continued: “With investment, the new hydrogen furnace technology could replace the need for blast furnaces altogether. The tools we are using and our links with industry mean that this project could scale up these technologies for commercial use quite quickly. This is crucial as we all know that time is of the essence in the drive to cut carbon emissions.”