Residual gases with low heating values resulting from steel production plants are presently poorly valorised, although they represent an important energetic reservoir. These gases exhibit specific combustion characteristics as compared to conventional gases. These untypical properties make necessary transposing the combustion techniques which are presently used. The proposed project aims at identifying, by means of experimental and numerical techniques, technological solutions for exploiting in an optimal way these gases in steel reheating furnaces, over a large spectrum of operating conditions. Experimental databases will be acquired at laboratory and semi-industrial scales. In parallel, fundamental numerical studies will allow characterising the interactions between chemistry and turbulence for these gases. This will feed the development of a micro-physical model, which will be validated and implemented in a three-dimensional simulation code used for designing and optimising industrial installations. The obtained numerical tool, which will be able to characterise in detail the interactions between chemistry, turbulence and radiation will be used by the industrial partner for identifying technological evolutions of burners and industrial furnaces, with the final objective of minimising pollutant and greenhouse gas emissions.

Refractory materials are key enablers for high temperature industries such as Iron & Steelmaking (I&S). Refractories are sophisticated materials designed and optimized to sustain severe operation conditions inducing complex combinations of thermo-mechano-chemical damage mechanisms. Nevertheless, refractory material consumption has been reduced over the last 50 years from more than 35 kg of refractories per ton of steel to about 10 kg/t in the European steel industry, while keeping safety of the utmost importance. The movement of the I&S industry towards Net-Zero emissions and digitalized processes through disruptive, breakthrough technologies will be achieved through the use of Hydrogen. The biggest challenge for the refractory industry is to continue to meet the performance expectations while, at the same time, moving to a more sustainable production direction. The complexity and urgency of these technology changes, highlighted by the European Green Deal, requires a Concerted European Action on Sustainable Applications of REFractories (CESAREF). A consorted and coordinated European network with steel, refractory, raw material producers and key academic poles will tackle the following key topics: • Efficient use of raw materials and recycling, • Microstructure design for increased sustainability, • Anticipation of hydrogen steelmaking, • Energy efficiency and durability. While creating new developments in the I&S and refractory industries, the network will train highly skilled doctoral candidates capable of communicating and disseminating their acquired knowledge. CESAREF will create a core team across the European refractory value chain, accelerating the drive towards the European refractory industries push towards sustainable materials and processes, as well as Net-Zero emission Steel production. This will help to create and secure sustainable employment in the European refractory and I&S industries.

Today, the European Union?s steel sector is a modern industry with its main customer base found within the EU home markets, particularly in high-end segments. However, challenges remain to keep the EU steel sector both competitive at a global level and climate-neutral, in line with the European Green Deal and the CleanSteel Partnership?s vision. The scrap usage in steelmaking is a common practice to improve the process? sustainability, as it decreases the use of virgin raw materials and boosts the circularity of the sector (decreasing CO2 emissions and electivity consumption). Nevertheless, the current trend in the EU scrap market points at a slight decrease in the pre-consumer scrap and an increase in the short- and long-term of the post-consumer scrap stream, due to an increase in steel consumption. Nowadays, these ?low-quality? scrap streams are not suitable for most applications, thus limiting their use in steelmaking. In order to increase the steel scrap recycling capacity and energy efficiency, while keeping EU competitive and safe in terms of raw materials imports, energy consumption and climate change impact, innovative technologies to ?clean? the scrap before it reaches the steel furnaces need to be implemented. CAESAR gathers up steelmakers, technology developers and research centers in a joint effort to validate, at full-size industrial scale, integrated scrap upgrading, sorting and characterization technologies, thus enabling to untap volumes of low-quality scrap streams in Europe, while keeping a high-quality product and generating valorization routes for all the non-ferrous fractions obtained, towards a zero waste steel sector.