Textile Recycling

Ever-more fashion retailers are establishing take-back systems – but the world is still a very long way away from having a closed-loop system for textile recycling. Collecting and sorting clothing, separating materials, recycling – virtually each of these steps demands quantum leaps both in terms of concepts and technology. Meanwhile, the mountains of used textiles are growing ever-taller because clothing has become a throwaway product. It is particularly for this reason that we must praise the many individual recycling activities that are showcasing the trend towards greater environmental awareness. A stock-take.

This figure provides food for thought: when talking about closed loop recycling, just one percent of clothing manufactured in 2015 was recycled into new fibers for the apparel industry. This is one of the findings of the British Ellen MacArthur Foundation, whose focus is to create an advanced closed-loop recycling system for the future. Its study estimates global fiber production for clothing alone over the examined period to be 53 million tons a year (Mta), of which 73 percent end up in landfill or are incinerated. Around 13 percent are recycled, usually turned into cleaning cloths or insulation materials, while a further 12 percent are cut-offs from production and excess stocks that are disposed of. One percent is microplastics, tiny plastic particles less than five millimeters in diameter that are released from synthetic textiles when washed and end up in our ground water.

It goes without saying that the study is in part based on estimates, as it is – even today – difficult to acquire reliable figures. However, the current trend does indicate that the overall situation is escalating. According to said study, the global consumption of textiles is expected to rise to 130 Mta by 2025 – faster that the world’s population in terms of percentages. A significant reason for this is the fact that the consumption of clothing has risen, particularly in the last decade. At the same time, the frequency of use for clothing has fallen rapidly: in the USA – a fast-fashion paradise – for example, an item of clothing is now worn on average just 40 times, while this figure has fallen from 200 to 62 times in China over the past 15 years. Clothing has become a disposable product.

And that has far-reaching consequences. Rising consumption of textiles goes hand-in-hand with an increase in the use of resources and a rise in the impact on the environment. Because the lion’s share of clothing manufacturing requires polyester and therefore crude oil, while cultivating cotton uses pesticides, fertilizers and a huge amount of water; and incinerating ever-more textiles also generates more CO₂ emissions. Add to this the fact that there will likely be fewer takers for the growing volumes of collected used textiles. Avid collectors such as the US, Germany and the United Kingdom have to date been exporting a significant proportion of used clothing to secondhand markets. However, their target regions – such as East Africa and India – are meanwhile starting to fight back, as their own textile manufacturers are suffering due to the existence of both these secondhand products and cheap new products from Asia. Ergo: used textiles warehouses are overflowing, prices are falling and sorting these textiles is becoming more complicated and expensive. And, in the European Union, new closed-loop system and waste framework guidelines are generating even greater pressure. To this end, the European Green Deal – within the context of the closed-loop economy action plan – demands that all EU countries adhere to prescribed recycling quotas and collect textiles separately to lower the volumes of household waste ending up in landfill.

Urgently required: closed-loop textile recycling
This large-scale picture clearly demonstrates that textile recycling is desperately required. This would allow the mountain of landfill waste to be further decreased, reduce fiber production, lower energy and water consumption and environmental pollution. However, this refers less to so-called open-loop recycling – in other words, the shredding and processing of textiles into lower-quality products (downcycling) for other industries – but specifically to closed-loop recycling, i.e. returning the recycled materials from clothing to the manufacture of clothing or quality textile products (upcycling). However, this ideal situation still requires technological further development. So, what is the textile industry doing today when it comes to recycling? What do the current technical solutions look like?

Re-manufacturing and take-back systems
Major fashion companies have been taking back used clothing and shoes for some time now, exchanging these for shopping vouchers. Here, service providers such as Germany-based I:Collect operate worldwide take-back systems with collecting, sorting and recycling solutions that sector giants such as Adidas, Levi’s, H&M and C&A are already utilizing. In the best-case scenario, the used textiles become secondhand goods, but also cleaning cloths and filling materials. In part, secondary raw materials – such as fiber blends, rubber and leather – are extracted.

This solution is considered an excellent example of progressive mechanical recycling, but also reveals its limitations. The sticking point lies in separating the materials. Clothing are usually made using mixed fabrics and are also often dyed or otherwise (chemically) finished. Breaking down the woven fibers into their specific components has not only been technically complex, time-consuming, energy-intensive and expensive (if it works at all) to date, the results have also been poorer in terms of quality than the original product. Hence, real fiber-to-fiber recycling is neither possible, nor economical.

From chemical recycling to fibers made from PET bottles
Chemical recycling promises to be a future solution, particularly with regards to polyester waste. Here, even contaminated or mixed plastics are thermochemically treated and converted back into raw materials such as oil and gas. With this, polycondensation processes can be used to make polyester for textile fibers. This would allow plastic waste – such as the plastic found in the world’s oceans – to be used as a resource and not just for the textile sector, but above all for the plastics industry.

The trend of transforming old PET bottles and textile waste made from polyester into new fibers and textiles has already been long underway. Many companies are already producing bottle flakes and recycled fibers for textile processing. 100-percent recycled products encompass the most diverse items, including jackets, sneakers, sports bras, luxury bags and also geogrids used for reinforcement in road construction. And many major apparel companies are focusing on recycling, sustainability and environmental awareness as a way of augmenting their brands. Machine manufacturers are also servicing this trend: to this end, Oerlikon Manmade Fibers offers sophisticated engineering solutions for mechanical recycling.

Numerous fiber types, numerous recycling models
Mohawk, a leading recycler within the carpet industry, also uses Oerlikon Manmade Fibers systems. The US company processes PET bottles into new carpets and recycles old carpets to create nylon and PP pellets for the automobile and furniture industries. American carpet maker Interface even boasts that its products are completely CO₂-neutral – from their manufacture all the way through to the end of their life – and promises that its textile products are fully recyclable.

Recycling apparel with a high ratio of cellulose, i.e. cotton and viscose, has also been shown to be successful. To this end, the Swedish company Circulose manufactures biodegradable cellulose for clothing in this way. Here, used clothing is shredded, buttons and similar things are removed, the items are decolorized and finally chemical pulped. The process generates cost benefits vis-à-vis producing wood pulp, but has disadvantages with regards to economies of scale compared to large-format systems.

As you can see, there are several concepts for the successful recycling of mono-materials, also with regards to fiber-to-fiber recycling. Although there are very few technologies aimed at recycling blended fabrics, there are however research developments. This places the focus on one thing above all: establishing functioning closed-loop systems requires the collaboration of all players across the entire value chain. This mission has already started: The European Green Deal intends that the fashion sector considers later recycling as early as the design phase. Politicians thus create legal rules and regulations on expanded manufacturer responsibility for textiles, also with regard to closer cooperation between producers and disposers.