The European Green Deal aims at zero net greenhouse gasses emissions by 2050. The steel and chemical industries are responsible for a significant fraction of these emissions. Mechanical and chemical recycling of end-of-life waste streams is an important feature in reducing these emissions. While end-of-life steel can easily be recycled, this is not generally true for end-of-life plastics and other wastes. The project aims to reduce emissions by increasing the recycling of unrecyclable waste streams, thereby tackling multiple problems at once.

This project investigates whether the waste fraction that cannot be recycled yet, can be used for both its energetic and its reductive potential as alternative reductant in a blast furnace. This would substitute for part of the cokes in a blast furnace, hereby decreasing the CO2 emissions. In the project, two routes for the production of alternative reductants will be investigated: the cokemaking route and the torrefaction route.

• In the cokemaking route pellets, supplied by the waste handling company, will be transformed into metallurgical cokes and by-products.
• In the torrefaction route, the pellets will be transformed into powdered coal.

The cokes and powdered coal take on the role of reductant and energy source in the blast furnace and as such drive the reduction process in the blast furnace. The result of this reduction reaction is that the oxygen atoms from the iron ore (FexOy) are transferred to the carbon and hydrogen atoms of the reductant, thereby forming CO, CO2, H2O and Fe (pig iron). Not only technical process aspects are important, also the economic feasibility needs to be evaluated.

The project fits in a bigger picture wherein the carbon loop can be closed completely. For this, the first step is to replace the fossil resources used in steelmaking, with carbon-based unrecyclable waste, as previously mentioned. This simultaneously addresses the large CO2 emissions of steelmaking and the lack of viable recycling options for non-recyclable wastes. The second step is the production of basic molecules for the chemical industry from steelmaking gasses, thereby creating the opportunity to close the carbon loop.

This vacancy aims to select a PhD researcher having an operations engineering, sustainable and innovative natural resource management, materials engineering, chemical engineering, business engineering, chemistry or a similar background. The goal of this PhD project is the investigation of the use of these alternative reductants in a blast furnace via techno-economic analysis, while keeping in mind which material parameters are essential for the steel production and waste handling. Your research will be counselled by the research group Sustainable Materials Science at Ghent University. The research is situated within the context of a European project showing an active cooperation with both a steel producer and waste handler.

More information: https://www.ugent.be/en/work/scientific/phd-student-92