From the Sector

Carbon fiber-reinforced polymer lamellas are an innovative method of reinforcing buildings. There are still many unanswered questions regarding their recycling, however. A research project by Empa's Mechanical Systems Engineering lab is now set to provide answers. Thanks to the support from a foundation, the project could now be launched.

The construction sector is responsible for around 60 percent of Switzerland's annual waste. The industry's efforts to recycle demolition materials are steadily increasing. Nevertheless, there are still end-of-life materials that, for the time being, cannot be reused as recycling would be too time-consuming and expensive. One of these are carbon fiber-reinforced polymer (CFRP) lamellas.

Making buildings "live" longer
The reinforcing method developed by Urs Meier, former Empa Director at Dübendorf, has been used in infrastructure construction for 30 years. CFRP lamellas are attached with epoxy adhesive to bridges, parking garages, building walls and ceilings made of concrete or masonry. As a result, the structures can be used for 20 to 30 years longer. The method is increasingly being applied worldwide – mainly because it massively improves the earthquake resistance of masonry buildings.

"By significantly extending the lifespan of buildings and infrastructure, CFRP lamellas make an important contribution to increasing sustainability in the construction sector. However, we need to find a way how we can further use CFRP lamellas after the buildings are being demolished," explains Giovanni Terrasi, Head of the Mechanical Systems Engineering lab at Empa. To achieve this, he wants to develop a method for recycling CFRP lamellas. Convinced by this idea, a foundation supported it with a generous donation. The project officially launched in October.

Gentle separation
First, a mechanical process will be developed to detach the CFRP lamellas from the concrete without damaging them. Initial tests at Empa are encouraging: After the lamellas were separated from the concrete, they still had a strength of 95 percent – even if they had already been used for 30 years.

Then, the demolished CFRP lamellas shall be used to produce reinforcement for prefabricated components. Terrasi's goal: saving thousands of tons of CFRP lamellas from ending up in landfills after the demolition of old concrete structures and reuse them in low-CO₂ concrete elements. After completion of the project, Giovanni Terrasi and his team – consisting of Zafeirios Triantafyllidis, Valentin Ott, Mateusz Wyrzykowski and Daniel Völki – want to produce railroad sleepers from recycled concrete, which will be reinforced and prestressed with demolition CFRP lamellas. This would give the "waste-to-be" material a second life in Swiss infrastructure construction.

Kelheim Fibres, a leading manufacturer of viscose speciality fibres, has joined Recycling Atelier Augsburg. Recycling Atelier Augsburg is a unique centre for research and development in the field of textile recycling. It is located at the Institut für Textiltechnik Augsburg an affiliated institute of Augsburg University of Applied Sciences. The two institutions founded the Recycling Atelier in June 2022 together with twelve partners from the German textile industry.

In the Recycling Atelier, the focus is on the triad of technical and ecological sense as well as economic benefit. In this way, the partners of the Recycling Atelier are standing up against fast fashion, outsourced corporate responsibility and a general decline in raw material quality, which often fuels downcycling - the low-quality reuse - of materials.

As a model factory, the Recycling Atelier Augsburg combines the most important processes of textile recycling and offers holistic and comprehensive research along the value chain," explains Georg Stegschuster, head of the Recycling Atelier Augsburg. The scientists research on all process steps of textile recycling: from material analysis to sorting, preparation and textile processing to sustainable product design. Comprehensive data collection and the use of artificial intelligence as well as innovative materials play a central role.

Kelheim Fibres is a producer of high-quality viscose fibres, which consist of cellulose, the main component of the renewable raw material wood, and are used worldwide for products in areas such as hygiene, textiles, and technical applications.

"In New Business Development as well as Fibre and Application Development, we follow the Open Innovation concept - the cooperation with the Recycling Atelier offers us an ideal platform for this. Here we work with partners to advance sustainability and performance," explains Maik Thiel, project manager at Kelheim Fibres.

Recycled cotton fibres are often very short or of uneven length, which makes further processing of 100 % recycled material a challenge. Adding speciality fibres from Kelheim Fibres should enable the production of high-quality new products, such as nonwovens. In the future, the fibres provided by Kelheim Fibres will also be made from recycled pulp.

The UK’s new Business Secretary, Grant Shapps has visited the Henry Royce Institute’ hub in Manchester to seal the second phase of R&D investment in the institute of £95 million. Fibre Extrusion Technology Limited (FET) of Leeds, England had previously installed its FET-200LAB wet spinning system at the University of Manchester site and this proved to be a focus for the Business Secretary’s interest, as he discussed the project with FET’s Research and Development Manager, Mark Smith.

This wet spinning technology enables fibres to be derived from sustainable wood pulp to produce high quality apparel and trials are now underway to perfect this process. FET is a world leading supplier of laboratory and pilot melt spinning systems, having successfully processed more than 35 different polymer types in multifilament, monofilament and nonwoven formats.

During his visit, Shapps spoke of the investment programme as a means of reinforcing the UK’s standing as a leader in advanced materials research, development and innovation.

“R&D investment is a critical way to turbocharge Britain’s growth. Growing an economy fit for the future means harnessing the full potential of advanced materials, making science fiction a reality by supporting projects from regenerative medicine to robots developing new recycling capabilities, right across the country. Today’s £95 million investment will do just that, bringing together the brightest minds across our businesses and institutions to help future-proof sectors from healthcare to nuclear energy.”

The Henry Royce Institute was established in 2015 with an initial £235 million government investment through the Engineering and Physical Sciences Research Council and the latest £95 million sum represents the second phase of the investment.

Opportunities being investigated by Royce include lightweight materials and structures, biomaterials and materials designed for reuse, recycling and remanufacture. Advanced materials are critical to the UK future in various industries, such as health, transport, energy, electronics and utilities.

The textile industry is the third largest consumer of plastics. While growth rates in the production of fibres and textiles are high, the circular economy has hardly become established in this segment. The EREMA Group is now intensifying development of recycling solutions for this application with their new fibres and textiles business unit. Currently, the focus is on PET fibre materials from fibre production and subsequent processing steps. Technologies for recycling mixed fibre textiles from textile collection sources are to follow in a follow-up project phase.

"With EREMA's VACUREMA® and INTAREMA® technology and PURE LOOP's ISEC evo technology, our company group already has an extensive range of machines for fibre and PET recycling applications. For ecologically and economically sound recycling, however, new technological solutions are needed to use the recycled fibres in higher-value end applications and to achieve a functioning circular economy," explains Wolfgang Hermann, Business Development Manager Application Fibres & Textiles, EREMA Group GmbH. The initial focus will be on PET, regarded as a key material for the production of synthetic fibres. The aim is to find recycling solutions that allow PET fibre materials to be prepared for reuse in PET fibre production processes. This is a significant step for the circular economy because PET fibres in textiles account for about two-thirds of the total volume of PET.

In this development work, the EREMA Group can build on existing know-how. Proven recycling technologies have been combined with a new IV optimiser. "This extends the residence time of the PET melt, which is particularly necessary in fibre recycling to efficiently remove spinning oils. Our recycling process also increases the IV value of the PET melt after extrusion back to the specific level that is essential for production of the fibre," explains Hermann. Waste PET fibre from production processes can therefore be further processed into rPET filament fibre, carpet yarn and staple fibre.

Fibre test centre with plant to test customers' materials
In order to accelerate development work, EREMA opened its own fibre test centre a few months ago, where a cross-company team is working on recycling solutions for fibre-to-fibre applications.

• The “new normal” by Südwolle: responsible, seasonless and high performance

The concept of seasonality in the F/W 2023/24 collection is increasingly vague, in favour of more functional categories in terms of performance, sustainability, innovative content and style.

Yarns are predominantly pure wool or blends, corresponding with the new concept of “dressing well” which is gaining ground among consumers – an individual style that promotes wellbeing at various times of the day, a fluid, personal idea of elegance, that fits daily activities with ease.

The new formal replaces the traditional suit with “smart casual” jackets and trousers -comfortable, and carefully cut, they feature quality materials that guarantee wearability as well as durability. Focus on these factors makes for more informed and less impulse buying.

The renewed interest in heritage is met with Südwolle's wool know-how and its basic essentials, updated to make them more sustainable by choosing certified fibres and chlorine-free anti-shrink treatments, for products with a longer lifespan thanks to domestic washing at low temperatures.

Sustainable innovation attentive to performance and durability goes hand in hand with the selection of earth-friendly recycled, recyclable and traceable materials blended with natural fibres.

Overview of the collection
The words inspiring the new collection are: sustainable, responsible, natural, recycled and high-performance.

A leading position goes to the OTW® line of weaving yarns made with Omega Twist® technology, developed and patented by Südwolle Group, which gives yarns enhanced performances in terms of reduced pilling, greater elasticity, strength and durability.

Espresso TEX Nm 48/2 (100% untreated wool,20.5μ) was created to value the authentic naturalness of wool. Made with undyed, untreated merino wool, it is a twisted yarn for weaving, ideal, for example, for flannel suits and jacket. It is available in 4 shades of brown obtained by mixing different percentages of untreated raw wool and undyed, naturally brown wool.
Eolo Nm 24/2 (100% wool 20.5 µ) is an example of circular production and reuse of recycled wool within the Karma project. Starting with in-house pre-and post-production waste, a partly carded, partly combed, product is created at Südwolle Group facilities where this type of process can be carried out.

Rhein GOTSNm 64/1 and Nm 64/2 (100% wool 19.5 µ) is the new pure woolyarn with GOTS –Global Organic Textile Standard certification, which certifies its organic provenance. The same traceable origin applies to Lerici GOTS X-COMPACT®Nm 60/1 (70% GOTS certified wool 19.5μ, 30% Schappe Mulberry silk), a glossy yarn with reduced pilling effect for improved anti-abrasion performance, obtained with X-COMPACT® spinning technology.

Performance paired with reduced energy consumption is the added value of SRP ClarkNm 60/2 (48% wool 23.5μ, 44% cationic polyester, 8% Donegal viscose), also available in a stretch version. The cationic polyester can be dyed blended with the wool, making double dying unnecessary and so saving on water and energy consumption. The addition of pre-dyed red, green or brown Donegal viscose to the blend creates a fluid look enhanced with slubbing and micro-nep effect.

Rosvic Nm 40/2 (98% wool 19.5μ, 2% Lycra®44 dtex) is a twisted yarn with Basolan treatment for comfort fabrics. It has a slightly textured surface with a contrasting or tone on tone micro mouliné pattern.

Key players among the circular knitting and hosiery yarns are Basak Nm 80/1(80% wool TEC. 20% polyamide 2.2 dtex), OTW® Barone GRS Nm 60/2(60% wool 23.5 µ TEC, 40% RENU™ recycled cationic polyester 2.2 dtex) and OTW®Concorde Nm 88/2(100% wool 19.3 µ TEC), available in the new colour cards.