DORNBIRN - At the 60th Dornbirn Global Fiber Conference (GFC), held virtually from September 15-17 this year, a range of new regenerated fibres coming out of Scandinavia in response to the new demands of the EU’s Waste Framework Directive, and to a lesser extent, the Single-Use Product Directive (SUPD) for single-use wipes and femcare products, were showcased.
Harald Cavalli-Björkmann, chief growth officer for Sweden’s Renewcell stressed that the four keys to achieving success for these new fibres are:
- Radical impact reduction
- Equal or superior quality
- Parity in pricing
- Massive scale
Renewcell is working with major brands including H&M, Inditex, Kering and Levi Strauss and plans to build a 60,000 ton capacity recycling plant in Sweden for the production of its Circulose fibre.
To make Circulose, discarded cotton textiles such as worn-out denim jeans are repurposed through a process akin to recycling paper, relying on a heavily-patented pulp production process. The incoming waste fabrics are broken down using water. The colour is then stripped from these materials, the slurry-like mixture is dried and the excess water extracted, leaving behind a sheet of Circulose. This sheet is then made into new viscose fibre.
Cavalli-Björkmann also observed that there is currently no recycling process available for turning used textiles back into textiles.
“Fashion needs solutions now,” he said. “The brands decide what gets made and put on the market and they are feeling the pressure, being consumer facing. They have posted ambitious sustainability goals and we are working in the supply chain to help them keep their promises.”
He emphasised that the Circulose process relies on the legacy of the pulp and paper industry, drawing on its know-how, technology and trade craft in order to de-risk and get to scale quicker.
“We are leveraging the existing value chain and using its infrastructure,” he said. “The SCA site where we are building the new plant was dedicated to printed paper where there is no longer growing value, but we are establishing this new cellulose processing industry based on its know-how and its people. This kind of transformation is happening in other industries too, and it’s vital not to discard existing assets that can be exploited in new product supply chains.”
With ABB technology, a former SCA paper mill will be transformed into the world’s first commercial-scale recycling plant for cellulosic textiles.
According to Renewcell’s preliminary calculations, textile fibres made from its recycled raw material use approximately 50 litres of fresh water per kg in production, compared to around 1,600 litres for cotton and 90 litres for non-cotton cellulosic material viscose.
With a maximum production capacity of 60,000 tons per year Renewcell’s approach could help to preserve around 90 billion litres of fresh water, the equivalent of 36,000 Olympic-sized swimming pools. The process also lowers waste, plastic pollution and both CO2 and chemical emissions.
“The ABB team proved its unique ability to deliver a complete automation and electrification solution based on its products and services,” said Patrik Lundström, CEO at Renewcell. “They have the knowledge, presence and experience that we need to keep this project on track, both in terms of budget and schedule. We also share a joint vision when it comes to resource efficiency, circular economy and sustainability so are pleased to be working closely with them on this exciting project.”
“As a technology company, we at ABB believe that electrification and automation technologies can play a key role in transforming industries and reducing their environmental footprint,” said Theodor Swedjemark, ABB’s chief communications and sustainability officer. “This contract allows us to apply our deep pulp and paper expertise and project experience to help Renewcell reduce its emissions and preserve resources, and ultimately change fashion for the better.
The process for recycling waste clothing is similar to pulp drying, breaking down cellulose in cotton and viscose textiles to recycle into new raw materials. This similarity enables Renewcell to use the existing infrastructure, including buildings and the supply and processing of raw water, waste water, compressed air and electricity at the SCA mill. This will be coupled with ABB’s paper and automation expertise, to manufacture recycled textiles that might otherwise have gone to landfill or incineration.
ABB brings its domain expertise from the pulp and paper industry, for example with specific technology to control the pulp dryer – a piece of equipment that was previously in use to dry raw wood pulp for paper and packaging – and quality control knowledge specific to the process. The customer requested weight and moisture measurement based on testing on a pilot machine.
Among the ABB technology that will be installed in the new plant is the market-leading process control system ABB Ability System 800xA that will provide operators with wide visibility and precise control from a central command centre to ensure that production is as resource efficient as possible, with less material consumption and reduced waste.
In addition, ABB’s PMC800 drive systems will reduce the cost of ownership over the automation lifecycle and improve energy efficiency during production. ABB will also supply ACS880 variable speed drives (VSDs) and IE4 super premium efficient motors, an efficiency level above the IE3 standard mandated by EU Ecodesign regulations. Combining high-efficiency motors with VSDs can typically reduce energy consumption in flow-controlled pulp and paper applications by 30% or more.
Finland’s Infinited Fiber Company, has also developed a process for turning cotton-rich waste textiles into high-quality, bio-based regenerated fibres, branded Infinna, and at the Dornbirn conference CEO and founder Petri Alava explained that it works with any cellulose-rich raw material.
This includes discarded textiles, but also used cardboard – which is increasing in volume as a result of the rise in internet shopping – rice or wheat straw, turning them into cellulose carbamate fibres with the look and feel of cotton.
“Infinna can be used with a variety of spinning technology and consumers can’t tell if the resulting fabrics are virgin or regenerated,” said Petri Alava. “It’s also a very versatile fibre.”
Infinited has already announced collaborations with leading fashion and textile brands, including Bestseller, H&M and Patagonia, as well as the Helsinki-headquartered nonwovens manufacturer Suominen, and in April 2021announced plans for a 30,000 metric tons per year plant in Finland, to be operational by 2024.
“We are now licensing the technology with some of the world’s leading producers in order to speed up,” Alava said. “We’re also firming up quantities and prices for our output from the new plant in Finland.”
Taking a different approach to cellulosics is a second Finnish company, Spinnova, the developer of a fibre technology which CTO Juha Salmela stressed involves no dissolving chemistry.
The development of Spinnova fibre originated from work to emulate the production of spider silk and spin filaments from cellulose.
The company was spun off from the VTT and built its first pilot scale plant in 2019, becoming a public company listed on the Helsinki stock exchange last year.
Spinnova technology enables fibre production from wood but also from textile waste or agricultural waste such as wheat straw.
The process is said to use no harmful chemicals and 99% less water than the cotton value chain. The fibre creates minimal CO2 emissions in production and is quickly biodegradable and contains no microplastics.
“Our fibres are based on wood, but also waste textiles and leather and our process involves pulping before mechanical grinding, with no dissolving pulp needed,” Salmela explained. “Elementary fibrils are released in the process via patented spinning nozzles and the water is evaporated out. This is a dry spinning process with no washing cycles involved.”
Spinnova has now partnered with Suzano, the world’s largest wood eucalyptus pulp producer to build Respin, a commercial scale fibre plant in Finland, with output to become available in 2022.
“The Respin production with Suzano will be based on pulp but we are also developing a second technology platform with KT trading, owner of the Ecco shoes brands based on leather waste, called Woodspin,” Salmela said. “This production route could switch from leather waste to textile waste without having to be changed.”
Earlier in 2021, Finland’s Stora Enso also announced that TreeToTextile, its joint venture with H&M and IKEA, would invest €35 million to construct a demonstration plant in Sweden, in a critical step towards commercialising a sustainable new regenerated cellulose textile fibre based on a process for spinning dissolving pulp
The novel process is designed to have low energy demand and low chemical needs and engineered to suit large scale production, including a recovery system for reusing chemicals.
The plant is under construction at Stora Enso’s Nymölla mill in southern Sweden and will have an annual production capacity of 1,500 tons.
At Dornbirn, Markus Mannström of the Biomaterials Division of Stora Enso pointed out that Stora Enso forests remove 1.5 million tonnes of CO2, while the company’s durable products for building solutions store a further 2.6 million tonnes and other products substituting for fossil-based alternatives save 17.9 million tonnes of CO2 each year. With the company’s value chain emissions amounting to 10.5 million tonnes, its overall footprint is –11.5 million tonnes, making its operations highly climate positive.
“What we continue to explore is how to generate more products that store more carbon for a longer period of time and how to innovate new products to make more out of less,” Mannström said.
With 23,000 employees globally, Stora Enso had sales of €8.6 billion in 2020, and first six-month sales of €4.9 billion. Its EBIT of €650 million in 2020 compared to €692 million for the first six-months of 2021 illustrates that the company has not been unaffected by the volatility of 2020.
It has six divisions – Packaging Materials, Packaging Solutions, Biomaterials, Wood Products, Forest and Paper, with the latter three viewed as its traditional businesses for cash generation and new growth to be achieved primarily in packaging and biomaterials.
A new Stora Enso innovation network focused on biomaterials has been established from scratch over the past six years, including two R&D centres, extensive laboratories and three pilot plants.
The company already has a strong position in fibre-based packaging, with products such as Formed Fiber and Biofoam providing sustainable solutions. In biomaterials, meanwhile, lignin from forestry is being primed for use in applications such as anode materials for energy storage, bio binders and new carbon fibres.
Stora Enso is anticipating a ten-fold growth in demand for anode materials due to the electrification of vehicles, and the Lignode plant it is currently ramping up in Sunila, Finland aims to see lignin-based products replacing graphite from coal mines.
Lignin is also employed with a crosslinker for NeoLigno, a new biobinder with wide-ranging applications in insulation, flooring etc., as well as the basis for the carbon precursor material Stora Enso is developing in a JV with Cordenka, the German manufacturer of high-tenacity, cellulose-based manmade fibres.
Once More pulp
Cellulosics fibre leader Lenzing has also been working with another Swedish pulp producer, Södra.
The two companies are developing a process for producing pulp from post-consumer waste with the goal of expanding to be able to 25,000 tons of textile waste per year by 2025.
The jointly developed pulp OnceMore pulp will subsequently also be used as a raw material for the production of Lenzing’s Tencel Refibra branded speciality fibres.
“One company alone cannot solve the pressing issue of textile waste,” said Lenzing’s Christian Weilach at the Dornbirn conference. “It is proactive partnerships like this that enable us to move forward and bring about real systemic change.”
By far the most widely used synthetic fibre and resin for the nonwovens industry remains polypropylene (PP), especially for AHPs and medical disposables.
Over the past few years, in response to the general pressure on plastics and synthetics, attempts to establish routes to the successful recycling and reuse of PP, as well as alternatives to the virgin fibre made from bio-based polymers, have understandably intensified.
For a number of years, however, cellulosics fibre leader Lenzing has been exploring the possibility of processing new types of biodegradable cellulose in exactly the same way that PP is turned into nonwovens for the majority of AHPs – i.e. by extruding them in a spunmelt system.
Lenzing has invested €26 million in a pilot line for its Web Technology process, which started up in 2018 and has subsequently filed around 40 patents related to the process.
At the Dornbirn conference, project manager Katharina Gregorich explained that in the process, dope cellulose is dissolved in MMO (n-methylmorpholine-n-oxide) and then extruded. The MMO is then washed out and recycled and the resulting web can then be hydroentangled.
The resulting spun nonwovens are biodegradable in water and soil and also compostable in just a few weeks, as well as being finish and binder free.
The Web Technology is also versatile, and Lenzing is manufacturing fine fibre (5-10 micron) webs and those based on coarser fibres of 20 microns and above. Multilayers are possible and the webs can be produced in basis weights of 16-100gsm.
As wipes substrates, these nonwovens offer good convertibility, fast wicking and homogenous lotion distribution in stacks,
Other target markets are cosmetic face masks, where the benchmark plastic carriers can be eliminated and filtration, to produce media with high dimensional stability, low elongation and good pleatability.
In AHP applications, 40gsm Web Technology webs are suitable for ADL (acquisition and distribution layers) where they provide good liquid spreading.