Wood is a hard, natural product and structurally very different from a soft fibre like cotton. As a result, turning wood into soft textile fibres that can be used to create fabrics and other textiles has always been a complex and chemically intensive process. First, the pulping process and chemicals have been designed to digest the wood raw material and produce a cellulose-rich pulp, dissolving pulp. After further processing, drying, shredding and pressing, the pulp is then rehydrated and the solution is forced through a spinneret and pulled into strands to create soft, straight fibres. Only then, after washing, are these fibres ready to be turned into fabrics and other textiles.
The production of textile fibres is big business. Including petrochemical-based fibres like polyester, acrylic and nylon (which make up around 64% of total output), as well as bio-based fibres like cotton, hemp and cellulose, global output in 2018 was over 100 million tonnes. But here’s the rub: manufacturing these fibres – whether they are produced, for example, as side-products from oil refining, or come from the production of viscose – are not considered very environmentally friendly.
A look to the future, however, suggests that the manufacturing of cellulose-based textile fibres, in particular, could soon be viewed in an environmentally more positive light. Through the use of extensive R&D, innovative chemicals (solvents), improved ‘closed-loop’ manufacturing methods, and new processing technologies, there is now the belief that future wood-based sustainable textile fibres could substantially reduce the environmental impact of regenerative cellulose fibre production - and create more sustainable textile industry.
The birth of spring
“We set up Metsä Spring in May 2018. It is a corporate venturing arm of the whole Metsä Group and the idea is to make equity investment through it into several external companies. Metsä Spring is essentially trying to find new technologies and business ideas that would strengthen, in a long run, the business ecosystem to which Metsä Group belongs. Some 95% of what I call the ‘prospects’ will most likely come from the outside of Metsä Group, but the first one just happened to be something that Metsä Fibre has been developing, i.e. the new textile fibre production concept. Now it has been transferred to Metsä Spring and it has become the first case,” begins Niklas von Weymarn, CEO, Metsä Spring.
The test plant, designed to demonstrate a new technology for converting paper-grade pulp into more sustainable textile fibres (with certain business-sensitive details currently a closely guarded secret), will be located next to Metsä Group’s bioproduct mill in Äänekoski, Finland, and is due to begin operations in late 2019.
“With regards to this new test plant,” says von Weymarn, “assuming we are able to deliver the results we desire for it, I think it is most likely that a possible future full-scale factory would be integrated to a Metsä Fibre factory and it would be using as raw material the pulp made by Metsä Fibre.”
Testing, testing, one, two, three
The new test plant, budgeted at EUR 40 million, a sum that includes both the construction and operational costs, is designed to produce 40 kilograms of next-gen fibre per hour. The plant is being built only to provide proof-of-concept that the new technology developed for the production of wood-based, sustainable textile fibres will work from a technical and financial feasibility perspective. Delivery of proof-of-concept at the test plant is a prerequisite for investing in a large-scale commercial production in the future.
Adds von Weymarn, “The proof-of-concept goes further. In addition to technical and financial aspects, we also hope to demonstrate a positive market reaction. Here the role of Itochu Corporation is vital. Although a drop-in product, it is still new and it will come with a new brand promise. In other words, what do the customer’s think about it, what are they willing to pay for it?”
Big in Japan
The Japanese Itochu Corporation are joint investors in the new test plant. States Hiroshi Morita, General Manager, Apparel Department 3, “Itochu Corporation has participated in this development almost from the beginning. Our role has been to support Metsä Group in achieving the global standards of textile fibres. Metsä Group is a world-leading actor in pulp production. Itochu Corporation, on the other hand, has a very long experience and deep knowledge of the textile fibre field, including existing wood-based textile fibres. Considering these two aspects, it made sense to join forces and go for a joint investment to stimulate this development.”
Itochu Corporation deals with various textile fibres from all over the world. Quite recently, Itochu Corporation decided to increase its presence in the fast-growing sub-field of sustainable textile fibres. To that end, Itochu aims to become a leading company in this sub-field.
Continues Morita, “This new development, together with Metsä Spring, is very innovative and unique. There are actually not that many new eco openings within the cellulosic textile fibre market. It seems to be difficult to develop such concepts from a production process point of view. Therefore, we thought this material has greater potential than any other materials in the current trend.”
The sustainability trend also ties in with how big brand owners are now rethinking how they should act in the future. Explains Morita, “There are three key elements, which are Eco, Sustainable and Traceability. Nowadays, companies who have influence in the market need to support the building of a sustainable world. As a result, companies are seriously working on how to reduce their environmental impact, as well as to reuse the limited natural resources. Therefore, ecological and sustainable fibres are getting more and more important. Additionally, all companies also have a duty to prove traceability.”
Setting new benchmarks on sustainable textiles
To that end, in terms of the needs for improved environmental factors like sustainability and recyclability in the future, there are currently high hopes for the joint venture.
Says von Weymarn, “I think we are in a good position, ecologically speaking. Compared to cotton production, most of the wood-based technologies are better, for instance, in terms of water and land use. Within the wood-based textile fibre sector, assessing the environmental footprint of the different fibre products is not that straight-forward. Even within the viscose sub-sector, external neutral expert organisations find some companies performing better than others. Needless to say, we naturally aim to have the most sustainable concept on the market. This stems from a few key differences, including, for example, the fact that instead of dissolving pulp we are using paper-grade pulp, and instead of dried pulp we use never-dried pulp.
Moreover, we are also developing a concept, in which the textile fibre production would be closely integrated to a bioproduct mill. This enables the clever use of various utilities and other resources. In this way, we can also ensure that all energy used by the sustainable textile fibre producing plant is 100% renewable energy.”
From the lab, to the pilot, to the future....
All that said, regarding the potential enhancements the test plant will reveal, a game-changing revolution is certainly not guaranteed. Encouraging results up to the present are not necessarily indicative of future success.
“There are a lot of critical parameters that you cannot measure at lab-scale,” notes von Weymarn, “because the equipment is not set up like that. For a proper measurement, you should be running the production process at least one month continuously, day and night, and a laboratory environment is not made for those kinds of normal industrial operations. For me, the proof-of-concept is achieved, if or when the test plant is running perfectly, and the customers love the product. Naturally, also the economic feasibility of the concept must be promising.”
DOING WOOD MORE GOOD
Come the end, the philosophy driving this entire venture is very simple to summarise in print (but immensely complex to realise in practice). At its heart is the understanding that raw materials derived from forests should be used for products that not only create high added value, but are recyclable, sustainable, financially feasible, traceable and ecological. There is quiet optimism that the new test plant will be the driver of change to allow new benchmarks to be set in future textile fibre production and sustainable textile industry.
“What we are now attempting is actually quite rare. The industry that produces wood-based textile fibres is an old industry. It produces annually roughly five million tonnes of textile fibres from wood, mainly utilising the 100-year old viscose technology. The second most spread technology globally is called Lyocell, which is also about 25 years old. The industry scene is still complemented by one single Cupro factory in Japan, which is most likely older than that. Our test plant is now leading the rise of a set of new technologies wanting to enter this very interesting market,” concludes von Weymarn.