Welcome back to the series ‘Sustainability in Denim‘. In episode 5, I took you on a tour to the new, fully sustainable jeans washing house in Germany, called “140Fahrenheit”, were Felix Holtgrave and his brother Maximilian showed me how state-of-the-art jeans washing is happening in the middle of Europe.

Today, I will share another experience with you, my trip to Renewcell, a textile-to-textile recycling plant on the Swedish coast.

No.6: a visit at Renewcell, the world’s first textile-to-textile recycling facility in Sweden.


Reduce Our Impact On The Planet And The People

It is no news anymore that fashion affects our planet massively; we produce too much, wear it too less, and throw away too quickly. Recycling is said to be one rescuer in that crisis. If we could use, what is already there, we would drastically reduce our impact on the planet and the people. But recycling technologies are in its infancy, the industry is far away from paper recycling or glass recycling rates. According to the Ellen MacArthur foundation, less than 1% of used garments are recycled into new garments. But there is a pioneer, a frontrunner on the horizon of textile waste: Renewcell.

I had the privilege to visit this impressive textile recycling factory in the middle of Sweden, which is producing a cellulose pulp out of 100% wasted textiles, called “CIRCULOSE®”. Join me on the recap of this exciting day:

After a 3.5h ride starting early in Stockholm through the lovely countryside of Sweden towards North, we finally reached Renewcell 1 in Sundsvall, called “the city of dragons”.

Upon arrival we drove through the massive storage halls, where thousands of clothing piles are waiting to get recycled to become a new garment.

renewcell sweden

renewcell sweden

Some of you might be sceptic: “Wait…used garments become new GARMENTS?” Yes, that is no typing error and no greenwashing; since November 2022, as the first company worldwide, Renewcell is recycling used garments (including lots of jeans) into material, which is processed into new garments again. So finally; clothing-to-clothing recycling is happening!

The process of Renewcell is to recycle old worn clothes into a pulp, which can be dissolved and respun into cellulosic yarn to create new fabrics and thus new clothes out of waste. Renewcell covers the process starting from wasted garments until pulp, based on old textiles only. There are cooperations with other factories to cover the next step in the chain, like create fibres and yarn out of that pulp. Renewcell sees itself as the link between waste and fibre production. Let’s see how the company got there!

The Renewcell Project That Began In 2012

Before scaling up last year, the Renewcell project began already 2012, when a couple of scientists started their journey to make the dirty fashion industry more sustainable. The world’s first 100% chemically recycled garment was developed 2014 in partnership with designers, fabric manufacturers and yarn spinners. The prototype of the “yellow dress” astonished the world. Interesting to the denim heads out there: the basic material back then was already blue denim, and to show, that chemical recycling enables to get rid of the original blue colour, the dress was dyed yellow, which marks the complete absence of blue.

One of the first partners in 2019 were H&M and Levi’s, who started pilot projects on a small scale. The 1st dress commercially created by H&M was available in March 2020, it was made with 50% viscose based on CIRCULOSE® and sold out quickly. Today, H&M is still a big shareholder of the company and benefits from the long partnership.

At the end of 2020, Renewcell entered the stock market successfully. 2021 and ‘22 were about growth and enabling access to that technology to many more fashion companies.

An old paper pulp factory in Sundsvall was bought and transformed into a big scale textile-to-textile recycling company, operating under 100% renewable energy. The paper factory ran until 2021, until the demand for paper decreased and the facility needed to close its production. There are quite some similarities between paper production and textile pulp production, so some equipment could be twisted and reused, but for the latest state-of-the-art machines, there was professional help from a specialized service team.

Since November 2022 CIRCULOSE® is produced and accessible for the fashion and textile industry. Today, Renewcell has cooperations with fibre manufacturers like Lenzing and the Birla Group and partnerships with Bestseller, Zara, Ganni and PVH, just to name a few.

At this point it should be said, that up to now, all garments made of CIRCULOSE® available are blended with virgin wood. That is mainly due to financial reasons, as CIRCULOSE® is more expensive than viscose made from virgin wood. But technically a composition of 100% CIRCULOSE® is possible in a garment. Customer demand and EU legislations may enable a higher recycling content for the future. Now let’s get into detail for every step of the process!

The Process Of Recycling

Currently the starting material for CIRCULOSE® is a combination of post-consumer garments and post-industrial waste like cutting scraps. The recycling process works because of cellulose, which is a component and main building block of plant-based fibres, no matter if virgin or wasted ones.

Cellulose is included in very high proportions especially in cotton fabrics, like jeans. As most garments are still sewn with polyester yarn, or also contain some percentage of synthetic content like elastane, Renewcell can work with up to 5% synthetic content. The plan is to expand that percentage to 10% to accept more kinds of fabrics.

So, in reverse, poly-cotton blends or wool-sweaters cannot be recycled, due to the high percentage of other fibres and missing cellulose, that’s why manual sorting in advance is a prerequisite to achieve the desired result. Most of the garments are from Pakistan and India, because there is a lot of textile waste and manual sorting is still the established practice.

renewcell sweden

renewcell sweden

The garments arrive via container ship on the company’s own port. Renewcell is sourcing from different waste traders and tries to buy and ship the material as efficient as possible by sea.

For recycling the whole garments are put into the shredder, no trims are removed, and no yarn is taken off, all metal items are shredded together with the garment.

In a second step these crushed trim-particles are removed and sent to metal recyclers. Synthetic particles are dissolved. The advantage is, that no additional manual process is needed, and no fabric gets wasted on cut-offs.

Unfortunately, due to security reasons we could not watch the shredding process. Additionally, the air quality is quite impaired due to the fibre parts flying around.

The shredded and separated cellulose-rich textile material is now entering the wet process of five cleaning and bleaching steps, where the proportion of water is 90%. Renewcell works as sustainable as possible and uses ozone technology besides other chemicals to remove the colour pigments.

Technically the colour of the fabric waste does not need to be removed. If only new jeans would be made from old jeans, for example, the indigo could stay and just get overdyed in the warp yarn. But as Renewcell is recycling all cotton waste and selling its pulp to different fibre and yarn manufacturers, a white colour is the easiest and more widely sellable.

Visually the wet pulp mixture now resembles common wood pulp, like paper mache. And that makes sense, as the building blocks are the same: Cellulose.

The next step is drying, as the humidity in the material needs to be reduced to 10% to create a material with the look and feel of a thick, grained but soft paper. The dryer is the largest machine in the factory, a remnant from the paper factory and maybe 50 – 60m long.

Afterwards the dry pulp plates are cut into pieces, piled up and packed to be sent to partners in China or other countries, to become fibres, yarn, fabric and finally new clothes.

The details of the process of mechanical and chemical recycling of 100% wasted garments into pulp on a large scale is unique worldwide and handled very confidential.

renewcell sweden

Today, 3500 tonnes of waste are transformed into CIRCULOSE® every month, but up to 5000 tonnes are possible.

The factory is getting more and more partnerships and 250 products containing CIRCULOSE® are on the market already. The holistic approach of Renewcell is to double that number until the end of 2024.

But the company has even more goals; the majority of textile waste should origin in post-consumer garments and be sourced from Europe, to further reduce the impact and make fashion circular.

Renewcell wants to close the loop, a completely infinite loop. At the moment it is not possible to recycle a CIRCULOSE® garment again into CIRCULOSE® pulp, as the process slightly varies by using viscose as an original material instead of cotton fabric. But its on the agenda, and Renewcells latest successes speak for themselves.

I am still deeply impressed by that day and the implementation of circularity. Might the future of Renewcell be bright, and the future of fashion be circular!

renewcell sweden

Progress And Developments Need To Be Used

Now it’s our turn to not only value that precious technology, but use it!

To all designers, developers, and buyers out there: Progress and developments need to be used! At the latest Kingpins in Amsterdam, denims with CIRCULOSE® inside were offered already from some mills; the hand-feel is lovely, and the look is authentic as is should be. Let’s use it, to be part of the circular movement and enable such amazing technology to enter the market!

And to all customers, interested in denim and jeans out there: If you spot a hangtag with the logo shown below. Give it a try and pay special attention, this is the start of circularity in the textile industry.

renewcell sweden

All images in the article by Sina Steidinger.

Stay tuned for more sustainable alternatives in the denim world!

Written by Sina Steidinger
Sina Steidinger is a self-employed denim designer and sustainability manager based in Amsterdam. After working for several brands in Germany for the past decade, she recently moved to the Netherlands to be in the heart of the European denim capital and to contribute to the latest developments in sustainable fashion. She is currently designing for Mud Jeans, a Dutch brand, and pioneers in circular denim. As a consultant, she gives workshops and speeches and advices brands on their way to a sustainable future.