"Steel recycling is recycling par excellence. Where other materials such as plastic, glass, and aluminium are not infinitely recyclable without a lot of sorting and extra effort, steel is. In fact, lower quality steels can be made even better in terms of quality. We call this "upcycling" in the industry," says Judith Krale, new business manager for scrap at Tata Steel Nederland and responsible for the use of scrap in steel production.

‘Can deal’ contributes to 30% scrap use for green, circular steel

She is often referred to as the woman of 30%, because Krale works every day to achieve the goal of 30% scrap use in the production of cleaner, greener, and circular steel by 2030. This is ambitious, as in 2022 the share of scrap in Tata Steel's steel production was 17%. Krale states: "With new technologies for making green steel, we can also recycle more steel. So, we are always looking for more scrap, including packaging tin." To achieve this, Tata Steel Nederland has signed agreements with ten scrap companies in multiple countries: the Nederland, Belgium, Germany, and the United Kingdom. The majority of the tinplate scrap in this 'can deal' comes from the United Kingdom, as that country has been engaged in waste separation for a longer period and is therefore further ahead in waste separation than the Netherlands and its neighboring countries.

Increased steel density for a more sustainable end product

At Tata Steel Nederland, the old steel, to-be-recycled tin is called 'tin can shred' because the steel cans are crushed in a kind of industrial mincer and flattened into small pieces, with a higher steel density. This has the advantage that its processing in the Oxy Steel Plant is more efficient, which in turn contributes to a more sustainable end product.

Steel cans are the recycling champion of the Netherlands

In addition to the many advantages of steel food packaging, such as long shelf life (even outside the refrigerator) and therefore less food waste, steel cans are not only easily recyclable but also relatively easy and inexpensive to separate from other waste due to their magnetic properties. In the Netherlands, steel packaging is therefore the 'recycling champion'. Almost 95% of the packaging steel used in the Netherlands is recycled into new steel. This includes beverage and food cans, aerosol cans, and paint cans. Tinplate is therefore the most recycled packaging material.

Read also: Tata Steel deploys high-tech laser and AI for increased steel recycling

To be able to significantly increase the use of scrap in steel production in the near future, Tata Steel aims to further optimize the recycling process. A challenge in this regard is that much of the old steel, such as from old ships or railroad tracks, is too large for regular conveyors and difficult to analyze. Therefore, Tata Steel researches the use of digital laser techniques to analyze the composition of scrap directly from the truck. The process works as follows: the truck carrying scrap enters a specially constructed gate with industrial laser and analysis equipment. The laser vaporizes very small pieces of the steel locally, creating a 'plasma', a small local gas bubble containing all the components of the scrap. This can then be filmed and analyzed with special cameras. Subsequently, depending on the specific composition and criteria, the scrap can be optimally introduced into the recycling process.

AI and digital twins for reduced waste and more CO2 reduction

Tata Steel researcher Bernard Ennis states: "In this measurement and analysis process, AI is used to more quickly recognize and analyze specific types of steel based on visual characteristics, known as 'scrap image recognition'. The manufacturing process is digitally modeled, or simulated, and tested in a computational model using 'digital twins'. This innovative combination of laser, AI, and digital modeling allows for more efficient sampling, faster scrap deployment logistics, and improved product quality. Moreover, this leads to fewer process errors in scrap deployment and thus less waste and CO2 reduction." At present, the technique is being researched and developed under the 'DiGreeS program'. The first measurements with the ‘Laser- Induced Breakdown Spectroscopy’ are scheduled to take place in the first quarter of 2025, with the first results being announced. In 2026, the first prototype of the truck portal is expected to be ready for use, and the measurements and modeling will commence. Then, the implementation will follow, including the introduction of the digital twins modelled process.

'DiGreeS': Research with German and Austrian steel producers

'DiGreeS' is coordinated by the Fraunhofer Institute for Nondestructive Testing IZFP and aims to minimize the ecological footprint of the entire steel value chain through integrated digitalization. Within the 'DiGreeS' program, Tata Steel also collaborates with Saarstahl AG and the voestalpine Group. Saarstahl AG focuses on CO2 reduction of Electric Arc Furnace (EAF) techniques at Saarstahl-Ascoval through the use of artificial intelligence based digital models, while voestalpine Group researches energy efficiency and conservation in steel plate processing. Tata Steel will also utilize this new knowledge when replacing the blast furnaces and coke and gas plants with DRI and EAF in the near future, as the traditional steel production process undergoes transformation and coal is replaced by sustainable energy.