Disassembly lines
A research centre is testing and developing automated systems for dismantling textiles and leathergoods. These systems could unlock the tricky matter of preparing post-consumer clothing, footwear and accessories for recycling. The centre’s aim is to devise industrial-scale solutions that would make recycling in Europe more efficient and economically viable.
Clothes and shoes that can no longer be worn or sold are, in theory, fine fodder for being recycled into new materials. They would be but for the many, mostly manual, preparatory operations needed to convert them into a format suitable for regeneration. Clothes need to be sorted by composition and colour. The textile, leather and rubber components of footwear need to be separated. These processes, to name but two, take time, add cost, and have made it in practice nearly impossible to foster a viable recycling ecosystem, at least in developed countries.
French research centre CETIA was created specifically to develop automated solutions to replace manual operations. Its origins date back to 2017, when ESTIA, an engineering school based in Bidart, launched the Biarritz Active Lifestyle Integral or BALI Chair to investigate circular solutions for post-consumer apparel, footwear and accessories. It has found support among French companies, including textile technology provider Lectra Systems, footwear group Eram, and sports retailer Decathlon, among other local and international apparel, sports and footwear brands and retailers.
CETIA was created in 2021 by ESTIA and CETI, a European textile research centre, based in Tourcoing, its name is therefore not an acronym but the fusion of its two founding institutions. Two years later, in September of 2023, it inaugurated a research and prototyping platform, in Hendaye, in the south-west of France. “Circularity very early on became a focal point for our research, and specifically the need to unlock key bottlenecks in preparing goods for recycling,” Chloé Salmon-Legagneur, head of the CETIA, tells WSA. “At the time, there were few such technologies.” The CETI had pilot tested the recycling of white T-shirts made from 100% cotton or 100% polyester with Decathlon and children’s wear brand Okaidi. “A key takeaway from this project was that collectors and sorters do not separate items for recycling, but rather for reuse as rags or refuse-derived fuel (RDF). Sorting centres did not necessarily sort items by composition, and composition labels are often either missing or illegible,” she says.
Pilot lines for testing
Testing existing technologies and devising new ones thus became the mission of the research centre, now housed in a 1,200 square-metre building. With financial support from the New Aquitaine region (€900,000), French Producer Responsibility Organisation Refashion (also €900,000), and industry partners chipping in, it was able to invest €2.4 million in the acquisition and engineering of machinery to streamline the preparatory phases of recycling. With a team of just eight people, it has been working on optimising existing equipment and creating new devices for collectors and sorters or recycling facilities.
The centre operates three pilot lines. It has a Fibersort machine, created by Belgian company Valvan, a maker of sorting and baling systems for the textile and recycling industries. This technology sorts textiles by composition and colour using spectrometry at a rate of one item per second. The device at CETIA dispatches clothes into ten different bins. But it can only identify single-layer apparel, as it cannot ‘see’ or detect the composition of a lining or a double-layered item of clothing. A first sorting process is therefore necessary to remove all multilayer clothes, which represent 12% of apparel feedstock, says Ms Salmon-Legagneur.
Equipment by Dell’Orco & Villani, a company based in Prato, opens bales, removes impurities and shreds textiles at a rate of 600 kg per hour. “These machines are efficient, but they degrade the quality of the fibres, which means that a good proportion of virgin fibre would need to be added to make a new yarn,” she points out. “Our aim is to extract the highest quality secondary raw materials so that they can be reused to make new products.” Other solutions, such as grinding shoes, to make various types of flooring materials, and diverting low-grade textile fibres towards insulation, are always possible, but not preferred. “We need to extract high value from waste to pave the way to a circular economy,” insists the head of CETIA.
Prototyping new devices
In the quest to obtain higher quality secondary raw materials, CETIA was one of 18 partners participating in the EU-funded SCIRT (System Circularity & Innovative Recycling of Textiles) innovation programme. Its research has led to the development of a machine to automate the removal of disruptors. TRACE, as it is called, takes a photo of a garment laid flat, analyses the images to identify fasteners and decorations and then guides a laser beam that cuts these away. “When these pieces are shredded, the length of their fibres is preserved,” she explains. The research centre has a demonstrator of this device and has optimised it with additional sensors and artificial intelligence to better identify new materials.
Possibly the most impressive of the devices at CETIA is the Reshoes robot, designed in-house. This machine is programmed to identify the precise model of a shoe by drawing on a database and using machine learning. It can process sport and city footwear that is glued, stitched, injected or vulcanised. Once it has detected the shoes’ make and composition, it calculates the temperature and time for a passage in an oven (which can be from four to six minutes). A robotic arm then clasps on to a pair and tears the uppers away from the soles. Sewn soles are cut away by a water jet following a pattern calculated by artificial intelligence. In its current form at CETIA, it releases shoes from the oven every 30 seconds, and can thus process 120 shoes per hour. “We could make it go faster,” she says, “by installing two sets of ovens on two levels. It would then process a pair every 15 seconds.” The device is fully operational for athletic footwear, whereas city shoes are a bit more complicated, she notes.
The automatic identification of the specific model of footwear is the way forward for Ms Salmon-Legagneur. “We are confident that it is the best solution, and it is not expensive. The device consists of a conveyor belt and two cameras; there are no fancy robots or expensive sensors. This makes it relatively affordable for sorters.”
Reshoes will be all the more efficient in the future when shoes designed for disassembly become more common. “This will make it possible to cut away soles more precisely,” she notes, referring to tests conducted with Salomon’s Index shoe, which is designed for circularity.
Learnings from the development and operation of the machine could help brands revise certain design choices and manufacturing techniques to simplify dismantling. “When we run into an issue with a pair of shoes, we try to identify the origin of the problem. At times, a small tweak can make a product much easier to recycle,” says Pauline Arrouasse, an engineer at CETIA. Another issue, she says, is that brands do not always know what materials are used to make their products. “A rubber sole can be made from any number of different rubber-based compounds, and a brand may not be aware of the presence of other elements, metallic ones for instance.”
“For small brands that are just launching, it should not be difficult to design shoes that can be cleanly dismantled at the end of their use. But we need volumes, and for that we need big brands to apply this design thinking in their product development processes,” insists Ms Salmon-Legagneur. “With partners such as Decathlon and Salomon, we are on the right path to reaching the volumes that can justify this type of investment for a collector/sorter.”
The missing business model
The cost of preparing waste for recycling and low demand for recycled content remain major hurdles to a circular future. “We need to make these processes economically viable for both a recycler and for a buyer of recycled fibres and materials,” says Ms Salmon-Legagneur. But she is optimistic: “Brands say they want to increase recycled content in their products, and if collectors and sorters see a market opportunity, they may decide to invest in the necessary equipment.” She sees possible unlocks in measures such as modulated eco-fees that increase the cost of virgin raw materials. “This would financially benefit brands that purchase recycled ones.” Other legislation can play a role, such as banning the destruction of unsold products in France, which increases the volume of feedstock for recycling. Finally, she notes that there is also the possibility that virgin raw materials become scarcer in the future. Like the automated solutions CETIA is developing to prepare goods for recycling, here too, market mechanics may need to be tweaked or optimised before a working business model is found.
The Fibersort uses a near-infrared (NIR) scanner and algorithms developed by Valvan Baling Systems to predict the fibre concentration in each textile that is put on the scanner, including fibre blends.
Credit: CETIA
