At first glance, everything is going on as usual at blast furnace 8 in the steel mill in Duisburg: Steel cooks in shiny silver protective suits are poking open the bunghole at the blast furnace, and liquid red-hot metal and slag are pouring into the chute below - another batch of pig iron, on its way to be processed into steel. But only on the surface are we dealing with the old familiar blast furnace product. Beneath the surface is an innovative material, one that makes the finished steel greener, more climate-friendly and therefore more sustainable.
The Duisburg colleagues have developed two steels of this kind and added them to the already extensive product portfolio: bluemint® pure and bluemint® recycled. The hallmark of both materials is that their production releases significantly fewer greenhouse gases than traditional iron ore smelting.
The use of the alternative materials directly reduces emissions at the Duisburg site and thus also the CO2 intensity of the steel volumes produced. For bluemint® pure, this results in a balance sheet reduction of 70 percent in CO2 intensity. The savings method has been tested and confirmed by the international certifier DNV and complies with the standards of the internationally recognized Greenhouse Gas Protocol. With bluemint® recycled, the reduced use of coking coal leads to real CO2 savings of up to 64 percent. The corresponding certificate is issued by TÜV Süd.
For the use of HBI and the specially processed scrap product, only a few plant engineering adjustments were necessary with regard to logistics and transport of the feedstock. In addition, the scrap is subjected to an additional radiation protection test and the use of both products is also approved by an official permit.
The new products reflect the great importance Steel Europe attaches to climate protection. By 2045 processes and products are to be climate-neutral. In addition to the production of CO2-reduced steels, the conversion of steel production from coal to hydrogen is one of the declared goals. The first plant is due to start operation in 2025.
The future viability of thyssenkrupp Steel Europe and its employees also depends on how quickly the segment can be converted to green steel - not only because of the political and legal framework but also because demand from our customers is growing for it. Bluemint steels have already gone on a large scale to customers such as bath manufacturer Kaldewey, transformer specialist SGB-SMIT and the packaging industry. Production volumes of up to 500,000 tons of bluemint® Steel per year are planned between 2022 and 2024, depending on material availability.
"We are getting very good feedback on our CO2-reduced steels," says Marie Jaroni, who heads Decarbonization & Sustainability. "And the logic behind the product is also well understood." Now she would like to see "an industry-wide definition of green steel," she says. That would help differentiate Steel Europe's certified steels from other offerings on the market. Marie Jaroni: "The path to a climate-neutral steel mill is a mammoth project that also requires a lot of commitment, coordination and willingness to change from employees. But also one that is worth the effort."