greentec steel
Research projects for green steel production
5. June 2023
Research projects for green steel production
4 minutes spent reading
Sustainability
Volkmar Held
As a freelance writer, Volkmar Held reports for voestalpine on topics that move people. The content of his stories ranges from archaeometallurgy to future technologies.
At voestalpine, we are charting the way ahead for green steel. Our continuous research and development in advanced technologies supports the implementation of the “carbon-free by 2050” goal to 2030 and beyond.
We think ahead. Especially regarding our contribution to climate protection. Starting in 2027, we will use greentec steel to reduce our CO2 emissions. This will equate to 5% of Austria’s annual CO2 emissions, making greentec steel the biggest climate protection program in Austria. To achieve the goal of carbon neutrality by 2050, we are researching several new processes and investing in pilot projects that demonstrate new ways to produce steel. Below is a summary of three key projects.
The H2FUTURE hydrogen pilot plant started operation in 2019 at the Linz site. This project will test the production of green hydrogen on an industrial scale and subsequently its potential applications in the various stages of steel production and in other industrial sectors. H2FUTURE has now successfully started operating and is already producing green hydrogen.
"We are using the innovative power of our research and development activities to advance greentec steel—from regeneratively producing hydrogen to manufacturing hot briquetted iron (HBI) and crude steel. We have been involved in promising projects such as H2FUTURE and HYFOR for many years to achieve this.” Franz A., Head of Research & Development and Innovation at voestalpine"
Sustainable Steelmaking
Another research project is SuSteel, at the Donawitz site. SuSteel stands for Sustainable Steelmaking. The process is sustainable because it allows crude steel to be produced without emitting carbon dioxide. In just a single process step, a hydrogen plasma separates the iron in the ore from its attendant oxygen (reduction) and smelts it for further use—explaining why this process is called hydrogen plasma smelting reduction.
At the heart of the SuSteel project is an innovative hydrogen plasma technology
If SuSteel is developed sufficiently to become economically feasible, the International Energy Agency (IEA) calculates that this and similar technologies will make an important contribution to reducing emissions, because the byproduct of this process is not carbon dioxide but water. This research project is currently being operated in a discontinuous pilot plant with batch quantities of 20-50 kg. The project partners are K1-MET, Montanuniversität Leoben, voestalpine Stahl GmbH, and voestalpine Stahl Donawitz GmbH.
We are developing another project on the path to green steel together with the plant construction company Primetals Technologies, the metallurgical competence center K1-MET, and Fortescue Metals Group, the world’s fourth-largest iron ore supplier. At the Linz site, we plan to jointly build Hy4Smelt, a prototype plant for the emissions-free production of pig iron on an industrial scale.
Hy4Smelt und greentec steel
HYFOR (hydrogen-based fine-ore reduction) uses 100% hydrogen to reliably reduce iron ore concentrates. The project partners Primetals Technologies, K1-MET, Montanuniversität Leoben, and voestalpine Stahl Donawitz GmbH have garnered valuable experience in this process from operating the pilot plant. Even in discontinuous operation mode, the voestalpine Donawitz site produced up to 200 kg of HBI per hour.
Hy4Smelt takes things a major step further and on an industrial scale: HBI leaves the HYFOR plant and goes directly into the smelter. This novel smelting unit produces a product similar to pig iron, which can be processed further in the traditional converter process (LD). In Linz, a demonstration plant will be built that will be able to produce up to 4 tons of pig iron per hour in a continuous process.
Hy4Smelt, the combined HYFOR and smelter plant, exploits further technological advantages for carbon-neutral steel production:
"Unlike the EAF, the smelter operates under reducing smelting conditions and can therefore also process ores with a lower iron content—low-grade and medium-grade ores. These ore grades account for around 85% of the world’s iron ore supply. Harnessing them on an industrial scale for economically viable, CO2-free reduction gives us advantages in the global competition for raw material.” Thomas B., CEO Metallurgical Competence Center K1-MET"
Only the much scarcer supply of high-grade ores can be used as direct reduced iron (DRI) or hot briquetted iron (HBI) which, along with scrap, is an important input material for direct use in the EAF in the classic DRI-EAF steel production route.
As an added bonus, Hy4Smelt can use the waste slag as a carbon-neutral clinker substitute, just like in the blast furnace process in the cement industry.
Green hydrogen from Linz for steel production
Starting in the mid-2030s, the International Energy Agency (IEA) proposes introducing green hydrogen “as a primary reducing agent on a commercial scale”. Its consumption in the steel industry will therefore increase significantly. However, on a global scale, the amount of hydrogen currently produced from water using the low-emission electrolysis route powered by green electricity is in the low single-digit percentage range.
“These statistics challenge us,” states Head of R&D Franz A. “We are expanding the H2FUTURE plant in Linz to include a compressor unit and suitable storage options. This will allow us to continuously supply the Hy4Smelt demonstration plant with green hydrogen from our own production, even when the renewable electricity supply fluctuates.”
greentec steel with top quality
Naturally, we are already ensuring that we will be able to uphold our quality promise using future steelmaking production routes. In around 150 melts from blast furnace converter technology, metallurgists have produced steel “just like that from an electric arc furnace” and analyzed more than 10,000 individual samples. This makes it possible to check material properties and material behavior during processing, even before construction of the EAF begins.
Volkmar Held