Hundreds, nearing on thousands, of tonnes per month. While still marginal, the volumes of textile waste recycled into new fabrics by denim mills have dramatically scaled up in recent years.

Major forces are driving the scaling of textile-to-textile recycling and the denim industry arguably leads other apparel sectors. Thanks to experience gained through the Dutch Denim Deal, the integration of reclaimed cotton fibres into new fabrics is becoming something of a standard. The baseline chosen by the project, which is now expanding globally, is to make 20% a minimum threshold for recycled content. Denim mills largely consider this a realistic target.

The momentum is real as full-scale recycling facilities have sprung up out of the ground at mills in Pakistan, India, Turkey and elsewhere in the past five or so years. Re&Up, a new company founded by textile group and Isko-owner Sanko, is the latest in the series. The Turkey-based conglomerate is setting the bar high as it plans to recycle 1 million tonnes of textile waste by 2030. Headquartered in the Netherlands and headed by Andreas Dorner, a former Lenzing executive, Re&Up intends to process both cotton and polyester. Combining these two fibre groups “means we can take 60% of all discarded textiles,” Mr Dorner tells Inside Denim. Sanko established the new company in Eindhoven to make it a European entity that will benefit from the bloc’s push for circularity in textiles.

Mr Dorner says the mixed feedstock coming into a Re&Up facility will take one of two paths. If it is cotton-rich, it will be decolourised, its elastane content removed using a thermomechanical process, and then mechanically recycled. “If we can obtain raw cotton fibres measuring 20mm, they can be spun into open-end yarns,” he notes. If incoming waste textiles are polyester-rich, they will be thermomechanically recycled. Here, too, shredded feedstock will first be decolourised, elastane removed, and then heated to separate the polyester, converted into chips, from the cotton, which, in the form of cellulose powder, will be sold to manmade cellulosic yarn producers. This technology is the fruit of a collaboration between the Hong Kong Research Institute of Textiles and Apparel (HKRITA) and Sanko engineers to optimise a method that, as its name implies, combines heat and mechanical processes to melt synthetic textiles back into fibre-grade polyester chips.

Sanko currently recycles 80,000 tonnes of cotton, polycotton and polyester waste per month in Turkey, says Mr Dorner. This is a far cry from 1 million tonnes, but the group plans to set up recycling hubs around the world in the coming years to expand capacity and reduce shipping and logistics. It envisions establishing Re&Up hubs in Central Europe, close to its customers, in Mexico, to serve the Americas, and eventually in Asia. Shipping waste across borders is not sustainable, adds to operating costs and is often simply illegal, the company points out.

Re&Up is casting a wide net over the textile waste it plans to treat, but used jeans are a key focus for the company. “This industry has an advantage over other sectors and it also has a head start,” says Mr Dorner. “Denim mills have been investing in recycling for the past five to ten years. This industry uses a limited range of raw materials, and it is also highly concentrated and vertical, so innovation can go fast.”

A new industrial landscape

In the past few years, many denim mills have built their own recycling facilities. Turkey-based Kipas has worked closely with its partner Säntis Textiles to develop a machine, RCO100, that improves on existing shredding techniques. Its recycling plant in Kahramanmaras can process 30 tonnes per day on two shredding lines that take in the mill’s own waste and post-consumer goods from “trusted sorters and brands to eliminate any concerns about hazardous chemicals,” Yücel Bayram, the company’s head of denim sales and marketing, tells Inside Denim.

The mill’s regular denim fabrics contain a minimum of 5% recycled content. A second tier of fabrics combines 15% pre-consumer waste with 5% post-consumer, blended with virgin cotton. It also offers 100% recycled cotton denims made entirely from pre-consumer fibres or from a mix of pre- and post-consumer waste, he says. Some of these are blended with recycled polyester, and the company is currently building a plant to recycle the synthetic fibre.

Soorty operates an industrial scale recycling facility in Pakistan, where it is based, and now markets its reclaimed cotton fabrics under the brand SecondLife. “The current capacity of this unit is 900 tonnes per month,” says Ebru Debbag, head of sales and marketing, which makes it roughly equal to that of Kipas. It generally runs 70% post-consumer and 30% pre-consumer waste, although she says this proportion can change depending on demand. The overarching goal, she insists, is to “increase the use of textile-to-textile recycled materials”. She further points out that Pakistan could be an important cotton recycling hub and estimates that capacity could be in the order of 250,000 tonnes. Artistic Denim Mills is the local partner of Recover, a pioneer in marketing mechanically recycled cotton, operates a large-scale plant.
Circular Park, the ‘fibre recovery’ facility of Karachi-based denim maker Artistic Milliners opened in 2022. The 70,000-square-foot factory is equipped with advanced sorting and automated shredding machinery manufactured by its technology partner Laroche and it is powered by clean energy, the company says. This unit centralises all internal waste streams from the mill’s manufacturing operations and takes in post-consumer waste as well. At full capacity it can ‘recover’ 6,000 tonnes of fibre annually, or 500 tonnes monthly, the company says. “This facility covers all our recycled cotton needs,” says Saqib Sohail, in charge of responsible business projects at Artistic Milliners. A standard of 20% recycled content is not uncommon and offers customers the quality they expect, he notes. The proportion of post-consumer recycled content can go to 40% or 50%, but he says the fabric will lose some strength. Pre-consumer waste, however, can make up 100% of a textile. “Our experience and expertise is growing, and the reality is that post-industrial waste yields higher staple length fibre,” he says.

The origin and make up of pre-consumer textile waste is generally known, which makes it possible to ensure integrity of content and traceability. This is not the case for post-consumer waste (PCW). “Traceability is a challenge, as we don’t know where the original cotton came from. There is no easy solution for this, we would need to use DNA testing,” says Mr Sohail. For now, Artistic Milliners can certify the “location of collection” of discarded jeans, the only PCW it takes in, which traces the feedstock back to a collection and sorting point. The company is working with Reverse Resources, a reverse supply chain specialist, and a local university, to map a local supply chain for reclaimed waste and develop a traceability tool. “The recycling industry is very diverse and this project involves a lot of groundwork,” he says, adding that most post-consumer waste comes from outside of the country.

Sharabati, which operates a recycling unit in Egypt, faces a similar issue with regards to PCW. “Few clothes are discarded in the country, and it is not possible to import used clothing, as the authorities want to avoid then being sold on the local market,” says Ghayth Miro, Sharabati’s total quality control and sustainability manager. The mill is a partner in a United Nations Industrial Development Organisation (UNIDO) programme to increase recycling capacity in Egypt by offering training on the collecting, sorting and pre-processing of textile waste. Daily, the company collects 10 tonnes of post-industrial waste from its operations and buys 10 tonnes from other suppliers, including UNIDO centres. It manufactures 60 tonnes of fabrics having varying levels of recycled content every day, says marketing manager Dr Dilek Erik.

A member of the Dutch Denim Deal, Sharabati is aligned on making 20% recycled content an industry standard. “It is possible,” says Mr Miro, but he adds that brands need to be realistic in their demands. “Recycled content won’t work well in a smooth and flat fabric but it is fine for more authentic and slubby looks,” he notes. Producing high quality ring spun yarns with high recycled content is not “realistic”. But he believes improvements in pre-processing and innovation in machinery will, in time, make it possible to increase the proportion of recycled content without sacrificing quality. Looking ahead, and as a member of the Denim Deal 2.0, he adds that Sharabati “is one of the largest denim mills in North Africa, and we could be a part of a future North African recycling hub”.

Bossa and Orta, both based in Turkey, and both Denim Deal members, have been increasing their recycling capacities and networks. Bossa has focused its efforts on optimising shredding processes to achieve longer staple fibres. Besim Özek, business development manager said that a third of the mill’s production is GRS certified for pre- and post-consumer cotton. The mill’s transparency report for 2022 indicates that it was expecting to increase its recycling capacity to 240 tonnes per month.

Orta offers a wide range of denim fabrics having 20% post-consumer recycled cotton. “It is our ‘golden ratio’,” says Sebla Onder, marketing and sustainability manager. “It allows us to maintain quality and colour and avoids generating too much waste.”

Further unlocks needed

Mills are quick to point out that post-industrial waste is relatively easy to process and reuse, but post-consumer waste is an entirely different matter. Chemical contamination and identifying the original provenance of the cotton fibres pose issues, says Ms Onder, at Orta. The segregation and sorting of used clothing is far from optimal, notes Ghayth Miro, at Sharabati. He keeps a close eye on all new developments in automated separation and sorting machines. The presence of elastane and polyester-based stretch yarns is another difficulty raised by Saqib Sohail at Artistic Milliners. Kipas is said to be working on a hybrid mechanical and chemical process to remove the stretch component from feedstock. After the harsh processes that post-consumer goods undergo, fibre length has a big impact on the quality and aesthetics of a fabric. This is why many mills, including Kipas and Bossa, have been working on optimising shredding.

PurFI believes it has a solution that avoids degrading fibre length. The technology is in operation in Belgium, in a joint venture between local textile group Concordia and the US-based company. “We call this process ‘reverse spinning’,” says Jean-Baptiste Tuytens, global sourcing and supply chain manager for PurfFI Belgium. The method takes used jeans cut into pieces and slowly reverts them back into fibre on a machine that measures 160 metres long. “It is a slow and gentle mechanical recycling that preserves fibres. We lose only 10-15% of a fibre’s initial length,” he says. The company strives to obtain fibres that are at least 23 mm long to ensure a high-quality finished fabric.

Another key unlock needed is a lift on bans on the transportation of used clothing across borders. Their status, some say, should not be waste but rather resource. Many mills are keeping watch on the evolution of European regulations. “The EU Waste Directive will have an impact on our resources,” says Andreas Dorner, at Re&Up. “It means retailers will become our suppliers.” It should increase the volumes of unsold stock and post-consumer goods that are directed to collection and sorting facilities, at least in Europe.

In its 2023 Materials Market Report (formerly the Preferred Textiles Report), Textile Exchange estimates that 300,000 tonnes of recycled cotton were produced in 2022. A number in the hundreds of thousands, admittedly, but representing a mere     1% of global cotton production. This volume could be double, according to a report, “Scaling for Circularity”, by the Circular Fashion Partnership. It found that apparel manufacturers in Bangladesh generate around 330,000 tonnes of post-industrial cotton waste annually, and only 5-7% of it is recycled into new fibres. This is a huge untapped opportunity, the report rightly states. It does not, however, rule out possible issues related to contamination and provenance.

The denim industry has a natural preference for used jeans in the post-consumer waste it recycles into new yarns. Shown here, bales at Soorty’s unit.
Photo: Soorty 

Share this story: