Innovation for the future: How we recycle our blast furnace gases

With our innovative technology Carbon2Chem, we convert climate-damaging CO₂ into valuable resources. This way we are gradually making our steel production climate-neutral.

For the fifth time in a row, thyssenkrupp is among the 100 most active companies in the ranking of the European Patent Office. In 2019 alone, the group filed more than 600 patent applications worldwide. This strength in innovation and the aim of developing the technologies of tomorrow already today motivated our interdisciplinary team of experts from thyssenkrupp Plant Technology and thyssenkrupp Steel to develop their patented Carbon2Chem technology. The process for recycling CO₂ emissions from steel production and the chemical industry is one of more than 22,000 innovations protected by patents in the company's 125-year history.

thyssenkrupp has set itself a clear goal in terms of climate protection: We want to become carbon neutral by 2050 and reduce our emissions by 30 percent by 2030. One focus is on steel production – after all, this is where around 95% of the group’s CO₂ emissions are released. Under the name Carbon2Chem the experts from the thyssenkrupp Steel and plant engineering businesses have jointly created a sustainable solution to help turn the unpopular “climate killer” into valuable raw materials.

Since 2018, their innovation has been registered as a patent with the European Patent Office under the number PCT/EP2014/003318 and the name “Combined system for producing steel and method for operating the combined system”. For this process, the developers do not regard CO₂ as harmful waste, but as a valuable material. After all, the carbon contained in CO₂ is an important primary material for organic chemistry and essential raw material and by-product of steel production.

Simply explained, the patented plant network is used to break down the waste gases from steel production – also known as metallurgical gases – into their chemical components and, with the right process, turn them into so-called synthetic gases. These synthetic gases are valuable chemicals that serve as precursors for the production of methanol, ammonia or polymers. Substances, which can then be used to produce fuel, fertilizer or plastics.

These chemical processes sometimes require more hydrogen than is contained in the metallurgical gases. The additional hydrogen required is produced by water electrolysis, in which water is split into oxygen and hydrogen using electricity. Therefore, according to the invention, it is planned that the plant network will also have an energy storage system to cover the electricity demand.

The result: the climate-damaging CO₂ is no longer released into the atmosphere and instead is transformed into something valuable. The fossil resources that currently still provide the carbon for the chemical industry are thus no longer needed. In addition, the plant network allows large industrial plants such as steel or chemical plants to be used as energy buffers.

In the Carbon2Chem pilot plant, the patented process is already being used in practice today. In five to seven years, Carbon2Chem will be ready for industrial-scale use. The Federal Ministry of Education and Research is funding the project with more than 60 million euros.

thyssenkrupp's patent department is one of the oldest in the country. Each year the colleagues protect around 600 new innovations through patents.