From the Sector

The DITF is leading the joint project "DACCUS-Pre*". The basic idea of the project is to develop a new building material that stores carbon in the long term and removes more CO₂ from the atmosphere than is emitted during its production.       

In collaboration with the company TechnoCarbon Technologies, the project is now well advanced - a first demonstrator in the form of a house wall element has been realized. It consists of three materials: Natural stone, carbon fibers and biochar. Each component contributes in a different way to the negative CO₂ balance of the material:

Two slabs of natural stone form the exposed walls of the wall element. The mechanical processing of the material, i.e. sawing in stone cutting machines, produces significant quantities of stone dust. This is very reactive due to its large specific surface area. Silicate weathering of the rock dust permanently binds a large amount of CO₂ from the atmosphere.

Carbon fibers in the form of technical fabrics reinforce the side walls of the wall elements. They absorb tensile forces and are intended to stabilize the building material in the same way as reinforcing steel in concrete. The carbon fibers used are bio-based, produced from biomass. Lignin-based carbon fibers, which have long been technically optimized at DITF Denkendorf, are particularly suitable for this application: They are inexpensive due to low raw material costs and have a high carbon yield. In addition, unlike reinforcing steel, they are not susceptible to oxidation and therefore last much longer. Although carbon fibers are more energy-intensive to produce than steel, as used in reinforced concrete, only a small amount is needed for use in building materials. As a result, the energy and CO₂ balance is much better than for reinforced concrete. By using solar heat and biomass to produce the carbon fibers and the weathering of the stone dust, the CO₂ balance of the new building material is actually negative, making it possible to construct CO₂-negative buildings.

The third component of the new building material is biochar. This is used as a filler between the two rock slabs. The char acts as an effective insulating material. It is also a permanent source of CO₂ storage, which plays a significant role in the CO₂ balance of the entire wall element.

From a technical point of view, the already realized demonstrator, a wall element for structural engineering, is well developed. The natural stone used is a gabbro from India, which has a high-quality appearance and is suitable for high loads. This has been proven in load tests.  Bio-based carbon fibers serve as the top layer of the stone slabs. The biochar from Convoris GmbH is characterized by particularly good thermal insulation values.

The CO₂ balance of a house wall made of the new material has been calculated and compared with that of conventional reinforced concrete. This results in a difference in the CO₂ balance of 157 CO₂ equivalents per square meter of house wall. A significant saving!

* (Methods for removing atmospheric carbon dioxide (Carbon Dioxide Removal) by Direct Air Carbon Capture, Utilization and Sustainable Storage after Use (DACCUS).

At this year's JEC World, STFI will be presenting highlights from carbon fibre recycling as well as a new approach to hemp-based bast fibres, which have promising properties as reinforcement in lightweight construction.

Green Snowboard
At JEC World in Paris from 5 to 7 March 2024, STFI will be showcasing a snowboard from silbaerg GmbH with a patented anisotropic coupling effect made from hemp and recycled carbon fibres with bio-based epoxy resin. In addition to silbaerg and STFI, the partners Circular Saxony - the innovation cluster for the circular economy, FUSE Composite and bto-epoxy GmbH were also involved in the development of the board. The green snowboard was honoured with the JEC Innovation Award 2024 in the “Sport, Leisure and Recreation” category.

VliesComp
The aim of the industrial partners Tenowo GmbH (Hof), Siemens AG (Erlangen), Invent GmbH (Braunschweig) and STFI united in the VliesComp project is to bring recycled materials back onto the market in various lightweight construction solutions. The application fields "Innovative e-machine concepts for the energy transition" and "Innovative e-machine concepts for e-mobility" were considered as examples. On display at JEC World in Paris will be a lightweight end shield for electric motors made from hybrid nonwovens - a mixture of thermoplastic fibre components and recycled reinforcing fibres - as well as nonwovens with 100% recycled reinforcing fibres. The end shield was ultimately manufactured with a 100% recycled fibre content. The tests showed that, compared to the variant made from primary carbon fibres using the RTM process, a 14% reduction in CO₂ equivalent is possible with the same performance. The calculation for the use of the prepreg process using a bio-resin system shows a potential for reducing the CO₂ equivalent by almost 70 %.

Bast fibre reinforcement
To increase stability in the plant stem, bast fibres form in the bark area, which support the stem but, in contrast to the rigid wood, are very flexible and allow slender, tall plants to move in the wind without breaking.A new process extracts the bast bark from hemp by peeling.The resulting characteristic values, such as tensile modulus of elasticity, breaking strength and elongation, are very promising in comparison with the continuous rovings made of flax available on the market.The material could be used as reinforcement in lightweight construction.At JEC World, STFI will be exhibiting reinforcing bars that have been processed into a knitted fabric using a pultrusion process based on bio-based reinforcing fibres made from hemp bast for mineral matrices.

SGL Carbon relies on climate-friendly manufacturing processes in the production of its own carbon fibers. By using renewable energy, the carbon footprint of SGL fiber can be reduced by up to 50% compared to a conventional fiber.  

SGL carbon fiber is produced at the Lavradio (Portugal) and Moses Lake (USA) sites. When the Moses Lake site was selected in the 1990s, the use of hydropower as an energy source played a particularly decisive role. As a result, around 75,000 tonnes of CO₂ can be saved in Moses Lake by purchasing electricity from hydropower plants compared to a fossil fuel-based electricity mix.

As part of the consistent implementation of its climate strategy, SGL Carbon will be using a CO₂-neutral biomass system to generate energy from the beginning of 2024, which will make the production system, which was previously based on natural gas, more flexible and climate-friendly. At full capacity, the biomass system in Lavradio can save more than 90,000 tons of CO₂.

The raw material used is wood pellets, which are sourced from a radius of 250 kilometres via short transport routes.

The climate-friendly energy supply at the site in Moses Lake (USA) combined with the new biomass plant in Lavradio (Portugal) lead to a reduction in CO₂ emissions of up to 50% in the production of SGL's own carbon fibers compared to conventional fibers. With the investment in the biomass system, SGL Carbon is pursuing its climate strategy. The target is to save 50% CO₂ emissions by the end of 2025 compared to the base year 2019 and to be climate-neutral by the end of 2038. In the period 2019 to 2022, SGL Carbon has reduced its CO₂ emissions by 17%.

As part of the Aachen-Dresden-Denkendorf International Textile Conference in Dresden, the Chairman of the Walter Reiners Foundation of the VDMA, Peter D. Dornier, presented awards to four successful young engineers. Two promotion prizes and two sustainability prizes were awarded in the Bachelor and Diploma/Master categories. Academic works in which solutions for resource-saving products and technologies are developed are eligible for the sustainability prizes.

A sustainability prize worth 3,000 euros in the Bachelor's category was awarded to Franziska Jauch, Niederrhein University of Applied Sciences, for her Bachelor's thesis on pigment digital printing in denim production.

The promotion prize in the Bachelor's category, also worth 3,000 euros, went to Annika Datko, RWTH Aachen, for her work on determining the polyester content in used textiles.

Dave Kersevan, TU Dresden, was honoured with a sustainability prize in the Diploma/Master's category, endowed with 3,500 euros. The subject of his thesis was the development of a laboratory system for the production of needled carbon preforms.

This year's promotion award in the Diploma/Master's category, endowed with prize money of 3,500 euros, went to Flávio Diniz from RWTH Aachen. The subject of his Master's thesis was the feasibility of manufacturing ultra-thin carbon fibres.

The award ceremony 2024 will take place in April at the VDMA stand at the Techtextil fair in Frankfurt.

The combination of high strength and rigidity with sustainability and a neutral carbon footprint makes flax the ideal raw material for natural fibre-reinforced plastics. vombaur offers composite textiles made of this natural fibre for the automotive, wind power, construction or sports industries and many other sectors.

Flax fibres are rigid and tear-proof. They have natural bactericidal properties, are virtually antistatic, stain resistant and easy to spin. Humans have taken advantage of these properties to manufacture robust, stain-resistant and lint-free textiles. Between the late 19^th and late 20^th centuries, cotton largely replaced natural fibres. Because flax can be grown in Europe and consumes less energy and water than cotton production, the material's importance is currently growing again, for both clothing and composites. Regional textile value added chains in Europe – flax makes them possible.

Ideal mechanical properties
vombaur makes the mechanical properties of flax usable for lightweight design. Because flax fibres are particularly rigid and tear-resistant, they ensure great stability in natural fibre-reinforced plastics (NFRPs). And thanks to their low density of 1.50 g/cm3, the fibres weigh virtually nothing. On top of this, fibre-reinforced plastics are less prone to splintering than glass fibre-reinforced plastics.

Excellent carbon footprint
The cultivation of flax binds CO₂ and the production of natural fibre-reinforced plastics (NFRPs) generates approximately one third less CO₂ emissions compared with conventional fibre-reinforced plastics. Energy consumption is substantially lower. This saves resources. The use of flax fibre tapes by vombaur in lightweight design applications also improves the product's carbon footprint and contributes to a secure, regional supply chain.

Recycling without impacting on quality
Flax offers another sustainability benefit: more recycling cycles than glass- or carbon fibre-reinforced plastics – without impacting on quality. Thermoplastic fibre-matrix prepregs are melted and reused in the recycling process. The natural fibres can be used in other products such as natural fibre-reinforced injection moulded parts.

Sustainable product developments for many industries
"Orthoses for high-performance sports, high-tech skis, wind turbines, components for the automotive industry or aerospace, but also modern window profiles – the application scope for our lightweight design flax tapes is amazingly diverse", as Carl Mrusek, Chief Sales Officer at vombaur explains. "After all, wherever flax tapes are used, three key properties come together: light weight, strength and sustainability".

With the goal of making recycling of lightweight, high-volume fiber and flake recyclate much more economical and, in some cases even possible, Coperion has developed a new version of its ZS-B side feeder. Using the innovative ZS-B MEGAfeed, plastic recyclate with a bulk density under 200 kg/m³, long considered intake-limited and thus not worth recycling, can be reliably fed in large quantities into Coperion’s ZSK twin screw extruder and be concurrently recycled and compounded.

The ZS-B side feeder’s novel design makes it possible to feed very high rates of fiber and flakes, such as PA, PE, PET, and PP. As a result, the ZSK twin screw extruder’s high capacity can be fully exploited when the ZS-B MEGAfeed is used. Very high throughputs in both mechanical and chemical recycling of post-industrial and post-consumer waste are achieved.

Increased Throughput in Numbers
With a ZSK 58 Mc18 twin screw extruder, the throughput increase and thus the potential of the new ZS-B MEGAfeed becomes very clear. When recycling PA fibers with a bulk density of ~40-50 kg/m3, throughputs of 70 kg/h were previously achieved using conventional equipment. When the PA fibers were fed into the ZSK extruder using the ZS-B MEGAfeed, throughputs increased about fourteenfold to 1,000 kg/h. Similar results were achieved recycling carbon fibers with a bulk density of ~50-70 kg/m3; in this case, throughputs increased from 50 kg/h to 2,500 kg/h using the ZS-B MEGAfeed. When recycling PCR (Post-Consumer Recycled) flakes, throughputs increased from 50 kg/h to 700 kg/h, and from 80 kg/h to 1,300 kg/h with multilayer film flakes.

Key to Economical Recycling of A Wide Variety of Plastics
Plastics previously considered not recyclable are becoming a valuable raw material using the new Coperion ZS-B MEGAfeed. For example, PCR flakes or recyclate from carbon fiber-reinforced plastics can now be fed into the ZSK extruder at high feed rates and recycled economically.

In the case of mechanical upcycling, upstream processes necessary for compounding, such as compacting, melting and agglomeration, are completely eliminated using the ZS-B MEGAfeed technology. In this recycling process, flakes and fibers can be fed directly into the ZSK extruder, where they are melted, compounded, devolatilized, and filtered in a single step. In so doing, both investment costs and energy consumption drop. The production process becomes significantly more efficient. Moreover, the thermal product stress is reduced and recyclate quality increases.

Even when recycling PET, the feed rate is no longer a limiting factor. With the ZS-B MEGAfeed, PET flakes and fibers can be fed into the ZSK twin screw extruder in large quantities with no pre-drying or crystallizing, where they can be processed with the highest degree of profitability.

The ZS-B MEGAfeed can also feed large quantities of post-consumer waste, adding appreciable value to the chemical recycling process with the ZSKs. ZSK throughput rates are very high with the ZS-B MEGAfeed. Preheating of the recyclate via mechanical energy input of the twin screws thus becomes even more economical for further processing in the reactor.

Existing Coperion extruders can be retrofitted with ZS-B MEGAfeed technology to greatly expand their spectrum of applications and increase their throughput rates.

• Hexcel Composite Innovations for Aerospace Applications on Display at JEC World 2022: Hall 5, Stand J41

In late 2021, Hexcel announced an agreement with Fairmat, a deep technology startup, to build the capability to recycle carbon fiber prepreg from Hexcel European operations for reuse in composite panels sold into commercial markets, giving a second life to recovered carbon fiber. To do so, Fairmat has developed a virtuous recycling process, and a sample of its newly recycled material will be available to view at JEC World 2022. Hexcel will present an array of product innovations for aerospace and urban air mobility customer applications during JEC World 2022 in Paris on May3-5. These latest innovations demonstrate the company’s leadership in developing advanced composites technology for the aerospace market.

• Sustainability Focus on Recycling and Reuse
• HiTape® and HiMax® Reinforcements for OoA Processing
• Innovative HiFlow™ Resins for Continuous and Shorter Cycle Injection Processes
• HexPly® Prepregs for Primary Structure and Engine Applications
• HexTow® High Modulus Fibers HM63 and HM54
• Thermoplastics and Processing Innovations for Primary and Secondary Structures
• Lightweight PrimeTex® Reinforcements Solutions for Urban Air Mobility (UAM)

Sicomin has confirmed that eco-surfboard specialist NOTOX will use GreenPoxy 56 in its latest line of R-CARBON boards. The new NOTOX R-CARBON boards are the first to use 100% upcycled carbon fibre fabrics recovered from a production waste stream at Airbus.

NOTOX, founded in 2006 and based in Basque, France, has partnered with Sicomin to use GreenPoxy bio-resins in several earlier flax, cork, and bamboo reinforced boards. In a quest to now produce the most sustainable carbon fibre reinforced boards possible, NOTOX has signed a formal agreement with Airbus Nantes to purchase defective carbon fabrics that were destined for landfill.

The new NOTOX technology gives a second life to Airbus carbon fabrics that are declared unusable for aerospace applications due to short roll lengths, an inability to be pre-formed, or other defects. The upcycled materials are combined with Sicomin GreenPoxy 56 and Surf Clear hardener, producing an extremely clear, high gloss laminate with high mechanical properties. NOTOX use a precisely controlled wet lamination process with vacuum bag consolidation to wet out the upcycled woven carbon fabrics and minimise resin consumption in the manufacturing process.

In addition to selecting a high bio-content resin – GreenPoxy 56 derives 56% of its carbon content from plant sources – NOTOX has also sourced the most sustainable carbon fibre fabrics. Full life cycle analysis by NOTOX has shown that using waste carbon fabrics from Airbus is significantly more energy efficient than using other recycled short fibre carbon, confirming the importance of upcycling this key raw material.

Strict protective measures will make the industry meeting possible at the International Conference on Cellulose Fibres in Cologne on February 2 and 3, 2022. The latest innovations will be shocased: from hygiene and textiles to non-wovens and carbon fibre alternatives to lightweight construction applications. Online participation is also possible.

Cellulose fibres show an increasingly expanding wide range of applications, while at the same time markets are driven by technological developments and political framework conditions, especially bans and restrictions on plastics and increasing sustainability requirements. The conference provides rich information on opportunities for cellulose fibres through policy assessment, a session on sustainability, recycling and alternative feedstocks as well as latest development in pulp, cellulose fibres and yarns. This includes application such as non-wovens, packaging and composites.

Live at the conference, host nova-Institute and sponsor GIG Karasek GmbH will grand the “Cellulose Fibre Innovation of the Year” award to one of six highly interesting products, ranging from cellulose made of orange and wood pulp to a novel technology for cellulose fibre production. The presentations, election of the winner by the conference audience and the award ceremony will take place on the first day of the conference.

The conference sessions reflect the current topics of industry and research. “Strategies and Market Trends” provides an overview of the rapid development of cellulose fibres and their technological progress across the fibre market. An analysis of the key cost components of these fibres to benchmark against current cost levels will highlight future opportunities and challenges for novel textile fibres. The session will conclude with an overview of the industry's recent strategies to defossilize the fibre market.

The session “New Opportunities for Cellulose Fibres in Replacing Plastics”, focusses on questions such as: “What impact does the ban on plastics in single-use products have on the industry?” and “What are the latest regulatory issues and policy opportunities for cellulose fibres?”. This part of the conference presents new opportunities for the replacement of fossil-based insulating materials with cellulose-based technologies suitable for use in a variety of applications, from aerospace to mobility and construction.
Institutefor Ecology and Innovation

“Sustainability and Circular Economy” highlights crucial issues with regard to the overall goal of keeping the environmental impact of cellulose fibres low. A core theme of the session is the responsible use of wood and forests. With this objective, the five speakers discuss the importance of circular concepts for cellulose feedstocks. Exciting insights into the important “Hot Button Report” are offered by Canopy. The “Hot Button” report enables the producers of cellulose fibres to better understand the impact their raw materials have on forests and the climate development worldwide.

The full conference programme is available at www.cellulose-fibres.eu/program.

• Hightech textiles for future-oriented construction projects

Building shells, bridges, staircases, façades ... construction projects are exposed to enormous mechanical loads. Often there are also considerable climatic or environmental influences. This has prompted the increasing use of fibre-reinforced materials in construction projects. After all, besides many other exciting properties, they offer high mechanical rigidity, low weight and excellent corrosion resistance.

Tapes, tubulars, sections and 3D woven textiles by vombaur form the perfect basis for these innovative building materials. The seamless round or shaped woven narrow textiles made of high-performance fibres are extremely loadable because they have neither seams nor welds – and therefore no undesirable breaking points. Their surface properties are identical over the entire length. In challenging tasks, composite textiles by vombaur offer a lightweight solution that is as reliable as it is durable.

Safe and durable solutions for challenging applications
The potential applications for lightweight components in the construction industry are as numerous as the project ideas of the planning and construction teams.
•    Ropes and tensioning elements made of carbon fibre reinforced plastic (CFRP)
•    Reinforcement of building structures made of concrete, steel, wood or other materials
•    Sustainable restructuring of constructions and urban districts for bridges and buildings
•    CFC slats as reinforcements in case of repairs
•    (Filled) GRP pipes made of seamless round woven tubes by vombaur as columns/pillars
•    CFRP sections as steel girder substitutes
•    Hollow profiles with individually designed cross-sections
•    Glass fibre reinforced connecting elements for glazing to minimise expansion differences between the connecting element and the glass
•    Individual light wells

Implementing visions – with composite textiles by vombaur
As your development partner, vombaur facilitates innovative composites projects for challenging applications. In innovative and safety-sensitive industries such as automotive and aviation, chemical and plant engineering.  The composites experts at vombaur develop, create samples of and manufacture woven tapes and seamless round or shaped woven textiles by vombaur – in collaboration with the customer's enterprise development teams and individually for the respective projects. This is how novel and unique lightweight components made of high-performance textiles are created for visionary lightweight construction projects.

"Fibre-reinforced composites are the ideal material for future-oriented construction projects," explains Dr.-Ing. Sven Schöfer, Head of Development and Innovation at vombaur. "Their outstanding technical properties and design possibilities open up new and fascinating perspectives for construction projects. From building construction to civil engineering, from bridge construction to interior design. As an experienced development partner for sophisticated lightweight components, we at vombaur contribute our seamless solutions to these kinds of future-oriented projects."