Steel production with hydrogen: Industrial-scale ore reduction successful

In Namibia, the SuSteelAG consortium has succeeded in its first industrial-scale practical test to process iron ore – including lower grades – into directly reduced iron in a climate-neutral manner. This was reported by the Federal Institute for Materials Research and Testing (BAM), which is leading the project.

The international SuSteelAG (Sustainable Steel from Australia and Germany) project, driven by Australia, Germany, and Namibia, is developing a hydrogen-based direct reduction process under BAM's coordination. The aim is to decarbonize the steel industry, which is responsible for around seven percent of global CO₂ emissions.

Iron ore with low iron content

One of the sticking points, according to BAM, is that climate-neutral steel production has so far only been possible with premium ores, which have a high iron content of around 70 percent. However, these ores are scarce worldwide and correspondingly expensive. Furthermore, a blast furnace must be used, which in turn requires a cost- and energy-intensive pre-treatment of the ore into pellets. The process used in Namibia can, for the first time, also utilize lower ore grades, thus opening up a broader raw material base for green steel production.

Thus, in Oshivela, Namibia, in early April, it was apparently possible to process 80 tons of Australian iron ore into directly reduced iron in a climate-neutral manner using an electrically operated hydrogen rotary kiln. The untreated Australian iron ore had a comparatively low iron content of around 56 percent. It was refined into iron at a throughput of about five tons per hour.

Christian Adam (BAM), coordinator of the international SuSteelAG consortium, explains: “For the first time, we have achieved a scale that is interesting for industrial production and proven that the hydrogen-based direct reduction of low-grade ores can be operated economically – a key to accelerating green steel production, also in Germany. This also means there is no bottleneck in climate-neutral steel production due to the scarce availability of premium ores.”

In the next step, the iron refined in Namibia will be shipped to Germany and examined by Salzgitter Mannesmann Forschung GmbH. Prospectively, climate-friendly steel for cars and other products will be produced from the refined iron. In addition, RWTH Aachen (Chair and Research Area for Technologies for Mineral Processing - AMR) will investigate how Australian ores with lower iron content can be further optimized for direct reduction.

Participants and Sponsors

The hydrogen rotary kiln in Namibia is operated by project partner HyIron Green Technologies. The development and construction are largely attributed to the German industrial furnace manufacturer TS Elino GmbH. The iron ore was supplied by the Australian mining and technology group Fortescue, which is also part of SuSteelAG. In addition to HyIron GmbH, the SuSteelAG consortium includes the Fraunhofer Institute for Surface Engineering and Thin Films IST, the Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Heidelberg Manufacturing Deutschland GmbH, and HANSAPORT. SuSteelAG is funded by the Federal Ministry of Research, Technology, and Space (BMFTR) within the 7th Energy Research Program with around 4.5 million euros. The rotary kiln from HyIron Green Technologies in Namibia was built with support from the Federal Ministry for Economic Affairs and Energy (BMWE).

(kbe)