Steel production accounts for approximately 15% of industrial CO2 emissions. In Europe, this is about two hundred million tonnes per year. In recent years TNO, together with companies and scientific partners, has developed technologies to reduce these emissions in a cost-effective way. The European Commission now has a proposal in its hands to take an important next step.
This involves the further development of a previously proven energy-efficient separation and capture technique for CO2: Sorption Enhanced Water Gas Shift (SEWGS). In recent years it has been demonstrated among leading partners at home and abroad that the high-temperature adsorption process can help the steel industry to remove CO2 from the production process in a relatively inexpensive way. At the same time, the cost savings are considerable.
CO2 footprint significantly reduced
The project proposal INITIATE (Innovative industrial transformation of the steel and chemical industries of Europe) concerns a method that can significantly reduce the CO2 footprint of steel producers. It does so by linking SEWGS in a special way to the production of the bulk chemicals ammonia and urea, thereby coupling the steel industry to the chemical industry. The project demonstrates the use of the so-called basic oxygen furnace (BOF) gas for the production of urea. BOF gas contains hydrogen, nitrogen and CO2. During the process the SEWGS technology creates a flow of hydrogen and nitrogen, on the other hand, and a concentrated CO2 flow, on the other. TNO experts discovered that urea can be produced very efficiently from this flow. By using the BOF gas as a raw material for the production of urea, not only can the amount of CO2 released be reduced by dozens of percent but also a waste gas stream from the steel industry serves as a raw material for the chemical industry.
Technical, economic and environmental benefits
This method of production is cheaper and much more environmentally friendly than the usual way of producing urea from natural gas. Urea is a widely used fertiliser as well as a raw material in the chemical industry. Demand for it is rising. Steel companies can thus tap into an extra source of income and make money by reducing CO2 in their production process.
TNO, together with project partners, has investigated the technical, economic and ecological benefits. Making urea without natural gas leads to a CO2 reduction of at least ten percent thanks to this application. As soon as large infrastructure projects for the transport and storage of CO2, such as Porthos in the port of Rotterdam and Athos in the Amsterdam-IJmuiden region, are completed, the steel industry will be able to transport the captured CO2 to these sites and further reduce its footprint by seventy percent.
In STEPWISE and BOF2UREA, TNO worked together with research institute Swerim from Sweden, technology supplier Stamicarbon, steel producer ArcelorMittal Belgum and Kisuma Chemicals from Veendam. In STEPWISE it was demonstrated on an industrial scale that CO2 can largely be removed from the production process using the adsorption technology. The BOF2UREA project, which was completed at the beginning of 2020, showed that urea can be produced cost-efficiently from the waste gas BOF, resulting in much lower CO2 emissions. The INITIATE project builds on this. The intention is to build a demonstrator on an industrial scale to take the process to an even higher level and make it ready for market introduction.