ArcelorMittal plans to scrap the use of coke in steelmaking
Steel group ArcelorMittal has plans to build a pilot plant in Hamburg that will use hydrogen in its ore reduction process to produce pure iron as part of a construction project that is due to get underway in the third quarter of this year. In future, some of the gas could be supplied by a new hydrogen network that is being set up especially for the industrial park at the port.
Between mountainous heaps and expansive production halls on ArcelorMittal’s manufacturing site, situated on the industrial park south of the Port of Hamburg, lies the Midrex plant. All rusty-red towers and pipelines, the building is clearly the most photogenic feature in the complex – 1970s steampunk at its finest. But it’s not just for looks that the German facility is now the center of attention. Its still unusual technological process is set to form the basis for carbon dioxide-free steelmaking – aided by green hydrogen.
This move toward hydrogen could potentially lead to large environmental gains since steel production in Germany and the European Union still accounts for around 7 percent to 9 percent of total carbon dioxide emissions. Of this, most of the carbon dioxide is released not as a result of the energy input required, but from material processes. Capturing and sequestering the carbon dioxide would be one way to “clean up” steel manufacturing. However, carbon capture and storage is a controversial subject due to the question marks remaining over storage location and the security of carbon dioxide containment.
If the intention is to prevent greenhouse gas from being created in the first place, and thus truly decarbonize the process, the one option still available is the use of hydrogen. Because of this, the hydrogen strategies of the EU, Germany and northern Germany rank the steel sector as a high-priority area of focus, along with the chemicals industry.
In Hamburg, the direct reduction process has been used as a means of converting iron ore to metallic iron for several decades. Yet in Germany as a whole, this method, which was developed by the company Midrex, has remained a rarity. In the ironworks of the Ruhr, Eisenhüttenstadt and Salzgitter, ore is still smelted in blast furnaces. But now that environmental concerns are starting to encroach on the industrial sector, the benefit of the direct reduction technique is coming to the fore. In comparison to a blast furnace which uses virtually pure carbon in the form of coke to draw out the oxygen from iron ore, leaving behind carbon dioxide and pig iron, direct reduction is much less carbon dioxide-intensive.
What is direct reduction?
In this process, natural gas reacts with iron ore to produce water, carbon dioxide and pure iron. As a result, the pelletized ore is transformed into pure iron pellets with microscopic pores. The pellets look exactly the same as they did previously, just weigh slightly less. This is why they have earned themselves the name “sponge iron,” also known by the technical term “directly reduced iron” or DRI. If methane is substituted by (“by” instead of “for” – changed on May 18th because of translation mistake) hydrogen, then the reduction process can occur with zero carbon dioxide emissions. This is precisely what ArcelorMittal wants to trial in Hamburg.
The projected cost for the pilot plant is EUR 100 million, with construction due to start in the third quarter of 2021 and last until 2024. The facility is then planned to go into operation in the course of 2025, with output provisionally pegged at 100,000 metric tons of DRI a year.
Goal: carbon neutrality by 2050
ArcelorMittal’s ambition is to achieve net-zero climate impact from carbon dioxide emissions by the year 2050. This is just one of several environmental milestones the company has put forward: By 2030 the company plans to reduce carbon dioxide emissions in Europe by 30 percent – no mean feat in itself considering the range of measures needed to make this a reality.
… Read more in the latest H2-International e-Journal, May 2021
Author: Eva Augsten