Technically SPEAKING

Technical Fibers Introduce a Unique Set of Challenges for Recycling Goals in Fiber Circular Economy

By Chris Plotz

The hot topic of fiber recycling is not without significant challenges for textile fiber applications, like apparel and home goods. Yet, technical fibers introduce their own set of properties that will need higher consideration in the circular economy, due to the demand from specific industries for strength and high performance derived from synthetic properties.

Here, we will consider the formulation of technical fibers and what makes them a challenge to recycle, key processes and benefits in recycling industrial fibers, regulatory issues surrounding recycled industrial fibers, as well as how industrial fibers are creating both challenges and new opportunities.

Technical Fibers and Their Challenge

Technical fibers are synthetic or natural fibers that have been engineered to have specific physical, chemical, or mechanical properties that make them suitable for specialized applications in a variety of industries. Unlike traditional textile fibers, technical fibers are designed to provide specific functionalities beyond basic comfort and aesthetics.

Specifically designed to meet the requirements of exacting applications, such as aerospace, automotive, construction, and medical industries, technical fibers are typically synthetic. These fibers are known for their superior strength, durability, and resistance to harsh environments, making them essential to produce high-performance materials. However, the production of technical fibers can have a significant environmental impact due to the high consumption of energy, water, and other resources, as well as the generation of waste and emissions. Recycling technical fibers is an effective way to reduce this environmental impact and create a more sustainable life cycle for these materials.

The production and use of technical fibers also raises environmental and health concerns, particularly related to the use of synthetic polymers and chemi- cals. Efforts are underway to develop sustainable and eco-friendly technical fibers, as well as to improve recycling and disposal practices for end-of-life products.

Technical fiber recycling, also known as closed-loop recycling, is a process of recycling industrial and commercial waste fibers into new usable fibers, without any degradation in quality, which is a significant challenge. Technical fibers are typically made from materials such as polyester, nylon, and polypropylene, which are commonly used in the manufacturing of clothing, carpets, automotive parts, and other industrial products.

The Case for Recycling

Recycling technical fibers involves the process of collecting and processing post-industrial waste, end-of-life products, and surplus materials to recover the raw materials and convert them into new products. The recycling process typically involves several stages, including sorting, shredding, cleaning, and reprocessing. During the sorting stage, the materials are separated based on their composition, color, and other characteristics. Then, the materials are shredded into small pieces and cleaned to remove impurities and contaminants. Finally, the clean fibers are reprocessed into new products, such as yarns, fabrics, and composites.

One of the key benefits of recycling technical fibers is that it conserves natural resources and reduces waste. Technical fibers are made from non-renewable resources, such as petroleum-based plastics, which have a limited supply and contribute to climate change. Recycling these fibers reduces the demand for virgin materials and decreases the amount of waste that ends up in landfills or oceans. Recycling also reduces energy consumption and greenhouse gas emissions associated with the production of new materials, as recycled fibers require less energy and resources to manufacture.

Regulatory Considerations

In addition to the environmental benefits, recycling technical fibers also enables regulatory compliance. Many countries have regulations and policies in place to encourage or require the use of recycled materials in industry. By recycling industrial fibers, companies can comply with these regulations and demonstrate their commitment to sustainability.

As an example, the European Union (EU) Waste Framework Directive (WFD) is a comprehensive piece of legislation that sets out a framework for waste management in the EU. The WFD was first adopted in 2008 and was recently updated in 2018 to further improve waste management practices and increase recycling rates. The WFD sets targets for the reuse and recycling of waste materials, including textiles.

The European Commission is currently working on a new Circular Economy Action Plan, which was adopted in March 2020. This action plan sets out a range of new initiatives and legislative proposals aimed at further promoting a circular economy in the EU. As part of the Circular Economy Action Plan, the European Commission has proposed several legislative initiatives, including a new Sustain- able Products Initiative and a new EU strategy for textiles.

The Circular Economy Action Plan includes measures to address key sustainability challenges such as resource depletion, waste generation, and greenhouse gas emissions. It also includes proposals to support the implementation of the WFD and to further promote the use of recycled materials in industry.

While the U.S. may not have a comprehensive circular economy framework at the federal level, there are several laws and initiatives aimed at promoting sustainable waste management practices and encouraging the use of recycled materials, as well as growing interest in the circular economy model among businesses and other stakeholders.

Overcoming Obstacles in Recycling

There are obvious and indirect challenges associated with recycling technical fibers.

The recycling process can be complex and require specialized equipment and expertise, which can make it more expensive than producing new materials. The quality of the recycled fibers may also be lower than that of virgin materials, which can limit their use in certain applications. Additionally, not all technical fibers are currently recyclable, which limits the potential for recycling in some industries.

To overcome these challenges, it is important to invest in research and development to improve the efficiency and quality of the recycling process. This includes developing new technologies for sorting, cleaning, and reprocessing fibers, as well as improving the design of products to facilitate their recyclability.

The process of technical fiber recycling involves several steps, including:

1. Collection and sorting: The waste fibers are collected and sorted based on their type, color, and quality.

2. Cleaning: The fibers are cleaned to remove any contaminants, such as dirt, oil, and other impurities.

3. Shredding: The fibers are shredded into small pieces to facilitate the recycling process.

4. Melt extrusion: The shredded fibers are melted down and extruded through small holes to form new fibers.

5. Spinning: The new fibers are spun into yarn or fabric, which can then be used in the manufacturing of new products.

Recycling technical fibers presents several hurdles that are not encountered when recycling more conventional materials such as paper, glass, or metal. Some of the key challenges to recycling technical fibers include:

• Complex composition: Technical fibers are often composed of multiple layers of different materials, such as polymers, metals, and other additives. This makes these fibers difficult to separate and recycle effectively.

• Contamination: Technical fibers may be contaminated with dirt, oil, or other substances that can make them unsuitable for recycling.

• Difficult to process: Some technical fibers may require specialized processing methods, such as high temperatures or chemical treatments, which can be expensive and energy intensive.

• Limited demand: The market for recycled technical fibers is often limited, as they may only be suitable for specific applications. This can make it difficult to achieve economies of scale and make recycling economically viable.

• Lack of infrastructure: Recycling technical fibers may require specialized equipment and facilities that may not be widely available or accessible.

Despite these challenges, there are ongoing efforts to develop new technologies and processes that can enable the recycling of technical fibers more effectively. For example, some companies are exploring the use of chemical recycling methods that can break down complex materials into their component parts, while others are developing new applications for recycled technical fibers, such as in building materials or automotive parts.

New Carbon Opportunities?

There are many new commercial industrial fibers commercialized globally but few match the properties and end-of-life challenges as carbon. Carbon fiber is difficult to recycle because it is a highly durable and lightweight material made up of long, thin strands of carbon atoms that are tightly woven together. The properties that make carbon fiber so desirable in many applications – its strength, stiffness, and lightness – also make it difficult to break down and recycle.

Carbon fiber recycling involves recovering the carbon fibers from end-of-life carbon fiber reinforced polymer (CFRP) composites and repurposing them for new applications. Recycling of carbon fibers is gaining increasing attention as the use of CFRP composites continues to grow in various industries, including aerospace, automotive, and sporting goods.

There are two main methods of recycling carbon fibers: mechanical recycling and chemical recycling. Mechanical recycling involves the physical separation of carbon fibers from the polymer matrix using techniques such as milling, grinding, and pyrolysis. The recovered carbon fibers can then be used to produce new CFRP composites or other products that require high-strength and lightweight materials. The disadvantage of mechanical recycling is that the resulting fibers are typically shorter and may have lower performance properties than virgin carbon fibers.

Chemical recycling, on the other hand, involves breaking down the polymer matrix using chemical processes to release the carbon fibers. The resulting fibers are often longer and have similar properties to virgin carbon fibers. Chemical recycling methods include solvolysis, hydrolysis, and pyrolysis. The disadvantage of chemical recycling is that it requires significant energy and resources to carry out the chemical processes.

In addition to the recycling of carbon fibers, there is also research into the development of biodegradable CFRP composites that can be broken down by natural processes, reducing the need for recycling. However, these materials are still in the early stages of development and may not yet be suitable for many applications.

Predicting specific technologies that will be available in 10 years for recycling technical fibers is difficult, as the field of recycling and sustainability is constantly evolving and advancing. Recycling technical fibers is an essential step towards creating a more sustainable future. It conserves natural resources, reduces waste, creates economic opportunities, and promotes sustainable development. While there are some challenges associated with recycling technical fibers, these can be overcome through investment in research and development, education, and policy support.

MiniFIBERS is leading the way in industrial fibers from the creation, converting and recycling. We continue to innovate and solve problems that are sustainable, efficient, and impactful.

Chris Plotz is the Director of Technical and Business Development at MiniFIBERS, Inc. in Johnson City, TN. Plotz is a business leader with 25 years of technical product and business development in a number of industries. He is responsible for leading and supporting all segments of growth of MiniFIBERS markets including C.A.S.E., nonwovens, composites and textiles of both synthetic and natural fibers. He can be reached at cplotz@minifibers.com or +1 423 616 2171.