Is hydrogen the answer to the steel industry’s CO2 problems?

The steel industry is known to be one of the world’s largest CO2 emitters – it contributes around 8% of global CO2 emissions. One particularly problematic area is the thermal processing of steel, which generates up to 39 billion tonnes of CO2 every year globally as a result of the use of natural gas. Can hydrogen be the solution for this emission-burdened industry?

In the context of the Hydreams project, the Swiss Steel Group is taking a decisive step in that direction. The project, which has been funded by the European Union since April 2023, is investigating how steel production can be made more climate-friendly by means of substituting clean hydrogen for natural gas. Two different types of furnace (heating and annealing furnaces) and two different types of burner (pulse-fired and flame systems) are being tested for their efficiency using hydrogen.

The effect of hydrogen combustion on steel quality

The project represents the first comprehensive attempt to investigate the effects of hydrogen combustion on various steel qualities. According to Swiss Steel, there have been no comprehensive studies to date that provide evidence of the physical changes and possible deviations in steel properties when hydrogen is used instead of natural gas – for example, due to differences in flame speed, radiation intensity or the composition of the waste gases.
“The substitution of hydrogen for natural gas in thermal processing is not yet fully developed and harbours potential risks – including an increase in NOx emissions and possible negative effects on steel quality and the service life of the refractory materials in the furnaces,” explains Laurent Sieye, Sustainability Manager Ugitech, Swiss Steel Group. “These potential challenges are the very things that need to be researched – solutions need to found in the Hydreams project.”
The project comprises several phases – from laboratory tests in pilot furnaces, through CFD simulations and furnace modelling to industrial demonstration tests. Tests were carried out on 13 different steel grades in the first phase alone. No structural differences or changes in the composition of the steel samples were identified during these tests.
The Hydreams project will be carrying out a series of industrial trials over the next few years. Three demonstrators for different heating processes and product types (blooms, forging ingots and coils) are already planned. ##Operation of the first demonstrator (Demo 3) began in March 2025, and the first tests using blooms are scheduled for this summer. Demo 1 and Demo 2 will start in 2026.
The project is in line with EU targets to mitigate climate change and decarbonise the steel industry. This solution could be an attractive alternative to electrical heating, which poses technical problems for certain applications, such as excessive wear of electrical resistors at high temperatures that are too high or a lack of temperature homogeneity in the furnace.
In addition to the technical findings, the project will also deliver safety assessments, life cycle analyses (LCA) and cost analyses, which are crucial for a future market launch.
Source: Swiss Steel