Interview with Amrei Becker and Lukasz Debicki, ITA
Amrei Becker and Lukasz Debicki
From 2025, used clothing and other textiles will be collected separately throughout Europe to facilitate reuse and recycling.
What industrial recycling solutions for textiles are already available?
Lukasz Debicki (LD): Nowadays, used clothing textiles are either reused as second-hand goods or in the form of, for example, cleaning rags. In addition, there are various recycling processes. Clothing or home textiles are often mechanically recycled and processed into insulation or filling materials. The textiles are torn, which dissolves the fabrics down to the individual fiber. These can then be further processed into said nonwovens or – if the fibers are of sufficient length – into staple fiber yarns. Mixed materials can also be recycled this way. Furthermore, a lot of textile waste is also incinerated or landfilled.
Amrei Becker (AB): Mono-material industrial waste, such as fibers made of polyester or polyamide, which are produced during the ramp-up of the melt spinning plant, can be regranulated and a small percentage of it can be returned to the process. Recycling of waste is also possible in yarn production from natural fibers. Furthermore, there is a Chinese company that already carries out the chemical recycling of worn polyester uniforms. The textiles are made of 100% PET and are specifically collected for recycling.
Lukasz Debicki (LD): Nowadays, used clothing textiles are either reused as second-hand goods or in the form of, for example, cleaning rags. In addition, there are various recycling processes. Clothing or home textiles are often mechanically recycled and processed into insulation or filling materials. The textiles are torn, which dissolves the fabrics down to the individual fiber. These can then be further processed into said nonwovens or – if the fibers are of sufficient length – into staple fiber yarns. Mixed materials can also be recycled this way. Furthermore, a lot of textile waste is also incinerated or landfilled.
Amrei Becker (AB): Mono-material industrial waste, such as fibers made of polyester or polyamide, which are produced during the ramp-up of the melt spinning plant, can be regranulated and a small percentage of it can be returned to the process. Recycling of waste is also possible in yarn production from natural fibers. Furthermore, there is a Chinese company that already carries out the chemical recycling of worn polyester uniforms. The textiles are made of 100% PET and are specifically collected for recycling.
Which innovative processes are about to be launched on the market?
LD: Currently, the main processes under development are solvent-based separation and various chemical recycling processes. In solvent-based separation, the desired polymer is selectively separated with a solvent and then recovered. The product can be spun into new fibers. The process can be used for cellulosic as well as synthetic materials. The chemical recycling of synthetic textiles also seems to be very promising, as the polymers are broken down into their basic building blocks, the monomers, or short polymer chains, oligomers. These can then be repolymerized into new polymers without any loss of properties. The biggest challenge is dealing with interfering substances. Dyes in particular are difficult to remove completely. The dyeing behavior of the textiles made from the recycled material can then be somewhat different from that of virgin material.
How can we increase the amount of textiles for recycling? What are the biggest challenges for the recycling of textiles?
AB: The first step towards more textile-to-textile recycling is to increase the amount of collected textiles. This should not only include clothing or home textiles from the used-clothing container, but also technical textiles and broken waste textiles that today end up in residual waste. In Germany, about 75% of textiles are collected from private households. In many other European countries, the share is only 10 - 20%. In order to recycle textiles in a high-quality manner in the next step, clearly defined material flows are needed. However, it is almost impossible to generate these with today's material mixes. The so-called design for recycling with, for example, fewer mixed materials, recycling-compatible coatings or easily separable haberdashery is incredibly important. And not just in a small collection with a lot of advertising but little turnover, but as far as possible on an extensive basis.
In the future, the recycling fraction can be sorted by material type with the help of scanners. I imagine that fractions with a certain minimum proportion of a specific material will be sorted in this way. The next step in the future could be a preparation for recycling. By this we mean, for example, the separation of haberdashery or the increase of bulk density. Today, this is hardly done at all.
Depending on the fraction, we can then decide how to recycle. It is important that we match the corresponding waste fraction with the right recycling process according to ecological and economic aspects. We are also working on this at the ITA and we see that the robustness of many recycling processes is not yet sufficient to recycle textiles in a high-quality way – especially when it comes to the handling of textile-typical fiber mixtures and additives (see here) or other impurities from the production and use phase.
Last but not least, there is also the question of the location for recycling. On one hand, much of the waste accumulates here in Europe, but on the other hand, spinning plants, textile machines and garment production – at least for clothing textiles – tend to be located in Asia. Will these productions come back to Europe?
Is there some kind of timetable for when and how the European textile industry will become completely circular?
LD: Yes, a plan was recently published in the "EU Strategy for Sustainable and Recyclable Textiles". A complete circularity is a big challenge and partly dependent on the regulations and the acceptance in the industry and the population.
AB: An economy that recycles is also not necessarily a very sustainable economy. If we continue to consume much, tolerate an overproduction of garment textiles of more than 30% and the destruction of online returns, and then recycle these materials, it’s nice, but it does not help us to meet our climate and sustainability goals. Textile production has a high environmental impact and recycling should not be an excuse used by the fashion and textile industry or consumers to justify high consumption.
How do you see the role of the industry, and what is the role of the consumer?
AB: Consumers can influence the path to a circular economy by informing themselves and putting pressure on legislators and industry. But I have to say that this is not easy. The issue is infinitely complex. As part of the 2020 university competition of the Federal Ministry of Education and Research in Germany, we have set up an Instagram channel on which we post relatively easy-to-understand texts and photos about bio-based textiles and recycling: @sustainable_textiles. We want to use it to take non-scientists along on the journey to a textile circular economy.
LD: The industry must establish sustainable and economic solutions along the entire process chains. To do this, everyone has to work together. One step into this direction is the Industry Research Group (IRG) Polymer Recycling at the ITA. In the IRG, well-known companies from all stages of the textile process chain come together to gather information, establish networks and develop innovative approaches and solutions. Please feel free to contact us for more information.
The interview was conducted by Mechthild Maas, editor of TextileTechnology, with Amrei Becker and Lukasz Debicki of Institut für Textiltechnik of RWTH Aachen University (ITA), Aachen/Germany.
