Recycling of Fibre Materials

Fibres are used for a large variety of applications. Textiles, nonwovens as well as fibre reinforced composite materials are commonly used in daily life and in technical applications. The annual world fibre market amounts to about 60 million t including natural and man-made fibres. Due to increased ecological awareness and more severe legislations disposal of waste is increasingly avoided through the use of recycling technologies. This development also takes place in the field of fibre materials. However, proper processes for fibre recycling are not yet fully developed. Commonly end-of-life fibres are supplied for energetic utilization. This method is not favourable since the energy generated from burning is much lower than the energy required for fibre manufacturing. The paper presents the state-of-theart in recycling fibres. Available technologies for textiles, carpets, composites and end-oflife vehicles are reviewed. However, these technologies do not offer satisfying solutions in terms of economic and ecologic demands. Within this study product recycling of fibres obtained from tyres is investigated. It is demonstrated that fibres recycled from waste tyres can be converted from waste to a valuable raw material if processed properly. Characterization possibilities for recycled fibres are also presented. It is demonstrated that most methods cannot provide feasible results. In the course of this research project a system based on optical image processing has been adopted for the characterization of recycled fibres. Characterization is necessary for product and quality control. Lastly, an adequate application for the recycled fibre materials is evaluated in this study. By addition of fibres gained from waste tyres an improvement of bitumen properties was found. An economic benefit can be expected since recycled fibres can substitute expensive state-of-the-art solutions.