To open the second week of our Fibres and composites transforming industry series, Dr Stacey Konash introduces the increasingly popular circular economy concept. What will it mean for Australian composites users, their products and their business models?
The circular economy has been gaining attention with policymakers and economists as a way to address dependency on raw materials and to de-couple the use of resources from economic growth. The World Economic Forum defines circular economy as “an industrial system that is restorative or regenerative by intention and design. It replaces the end-of-life concept with restoration, shifts towards the use of renewable energy, eliminates the use of toxic chemicals, which impair reuse and return to the biosphere, and aims for the elimination of waste through the superior design of materials, products, systems, and business models. ”
Carbon fibre composites are materials that enable the construction of lighter products by combining the versatility of plastic (matrix) with the high strength and rigidity of carbon fibre (reinforcement). Lower weight means that, for example, vehicles (cars and aeroplanes) require less fuel to travel the distance, which in turn decreases the carbon footprint of the logistics industry. According to a 2020 report by Markets and Markets, the global carbon fibre & carbon fibre composites market size is projected to grow from USD 17.5 billion in 2020 to USD 31.5 billion by 2025, at a CAGR of 12.4% during the forecast period. Australian companies have captured some of this market already with, for example, Quickstep addressing the aerospace market and Carbon Revolution offering unique products to the automotive sector.
Carbon fibre composites start their life as a mixture of carbon fibre and polymer, both normally derived from fossil oil. However, the push to move away from using fossil-sourced chemicals resulted in the development of a commercial range of bio-resins and plant-sourced precursors for carbon fibre. Plant-sourced materials are considered sustainably sourced input materials for composites manufacturing. An alternative approach to sustainable sourcing of raw materials is the use of recycled/recyclable materials. Thus, Toray developed &+TM – carbon fibre made from post-consumer PET bottles. Recyclable resin options include high-temperature thermoplastics and vitrimers, i.e. a new type of thermosets with dynamic bonds. Using sustainably sourced raw material enables designers and manufacturers to decrease the carbon footprint of their product and ensure the supply of those raw materials.
Repair represents another approach to extending the useful life of the product and the material. Repairs of carbon fibre composites are widely used in the aerospace and luxury automotive sectors. Self-healing matrices or resins that are easy to remelt and repair represent the future direction in extending the life of composite parts. In addition to material innovation, the opportunity exists in repairing more mass-produced and relatively lower cost items such as BMW i-series cars, bicycles, racquets and other sports equipment. For these items, the cost of developing and performing procedures for inspection and repairs is perceived to be higher than the cost of replacing the item. Repairs require specialised composites-handling skills and an understanding of the material performance. Lack of trust in the repaired product and lack of consumer awareness are some of the barriers to more widespread repairs in consumer markets. Design for repair needs to ensure products compatibility with new materials that allow in-situ repairs.
Repurposing of carbon and glass fibre composite structures has emerged as an innovative way to extend the life cycle of these materials. Furniture, city architecture, and art sculptures are some examples of repurposing. To give one example, Lufthansa launched their upcycling collection of home furniture and lifestyle accessories from the parts of decommissioned Airbus. Windmill turbine blades have found a second life on children’s playgrounds, bicycle shelters, and bridges. Australian architects and construction companies can expand their portfolio of structural materials by including large composites parts.
Recycling is generally one of the least preferred circular economy strategies to recoup value. For carbon fibre composites recycling currently means downcycling as the properties of recovered material are not compatible with the manufacturing processes used for virgin materials. Although aerospace scrap is the major source of recycled carbon fibre, it is not possible to close the loop for carbon fibre composites through recycling in this market. However, due to the high strength-to-weight ratio, flexural strength, tensile strength, and cost-effectiveness recycled fibres find wide application in the automotive & transportation industry. They are used for floor, walls, roofs panels in cars and trains. JucSurf is making surfing boards out of recycled fibre. The future efforts in recycling technology development are mostly stimulated by social expectations and governmental regulations. The isolated geographical position of Australia and the small volume of domestic composite waste creates challenges in establishing the local recycling carbon fibre facility.
The New European Circular Economy plan advises businesses to adopt a circular economy approach with a wider, systemic view of energy and raw material flows through the supply chain. Environmental reporting is important for companies to communicate their values and circular initiatives to their supply chain partners. ISO14001 and Global Reporting Initiative are two of the most commonly used reporting frameworks. This type of reporting and certification is especially important when bidding for government contracts and entering the supply chain of a large OEM, like BMW.
Manufacturing process optimisation is often the outcome of environmental management system implementation. Smart manufacturing, smart sensors, digitalisation of manufacturing processes, and the creation of digital twins are all technologies that assist composites manufacturers in improving their manufacturing process and lowering their carbon footprint. Strong vertical supply chain integration supports better data exchange and higher transparency, thus minimising waste creation due to miscommunication.
Tracing the material throughout a product’s lifecycle and supply chain is another important capability to enable longer service life and better recycling outcomes. The miniaturised sensors combined with big data analytics capability create opportunities to monitor the health of composites and track them throughout the manufacturing process and beyond. Some examples include:
- embedded low-frequency RFID sensors that can withstand the temperatures and pressures necessary for carbon fibre composites manufacturing;
- microwires that allow contactless temperature and pressure measurements in carbon fibre parts during production, assembly, and service;
- piezo-ceramic sensors that detect damage, pinpoint its location and assess damage extent.
Tested in composites for decades, these systems have matured and are working to enable circular business models, such as product-as-a-service sharing and reuse. The advances in data analytics and in-situ monitoring together with non-destructive testing data allows us to trace the materials and parts and creates opportunities to develop a unified certification/testing framework for the used components.
To summarise, the circular economy creates the opportunity to increase the sustainability of the carbon fibre composites industry and to meet stricter environmental regulation and societal expectations. The move to a circular mode of operation entails the shift in both product flow and money flow through the business. The product flow looks at design, use optimisation and reverse logistics. The money flow involves business operations and business model transformation, such as servitisation, shared ownership and access to post-consumer products. The linear economic model is based on downstream cost reduction, resulting in a more competitive relationship with suppliers. By contrast, circular business is much easier when all the actors in a supply chain work together because new value is created through the joint process of assembling and disassembling. Switching to a waste-free economy necessitates transformations of supply chains and consumption patterns throughout the value chain: product design and production techniques, shared ownership and product-as-a-service models, repair and remanufacturing business activities, and recovery and recycling of materials. Process optimisation and waste minimisation efforts often require wider supply chain cooperation and may alter the company’s value proposition by incorporating business strategies, such as extending the product’s operational lifespan, repair, repurpose or remanufacture. While these are not novel strategies, their application to business opportunities has changed due to the availability of new materials and technologies. Strong vertical supply chain integration in the carbon fibre composite industry makes it particularly suitable to reap the rewards of circular economy.
Australian companies with an interest in carbon fibre composites can benefit by increasing the transparency regarding their environmental footprint and by staying up to date with raw material innovation, in-use data collection technologies, and end-of-life options. The advances in health-monitoring technologies combined with data analytics create the foundation for certified and thus more accepted repairs of carbon fibre composites, which in turn support the product as a service business model. New technologies for recycling carbon fibre composites will continue to be driven by tighter landfill regulations and recyclability requirements. By embedding circular thinking into all parts of their business early, the Australian carbon fibre composites industry can lead Australia’s circular economy transformation, supported by materials and chemistry innovation, digitalisation, traceability and smart manufacturing processes.
Dr Anastassija (Stacey) Konash is a Fulbright Coral Sea Scholar and Industry 4.0 Testlab Project Manager at Swinburne University of Technology.
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