A Review of Recycling Methods for Fibre Reinforced Polymer Composites

This paper presents a review of waste disposal methods for fibre reinforced polymer (FRP) materials. The methods range from waste minimisation, repurposing, reusing, recycling, incineration, and co-processing in a cement plant to dumping in a landfill. Their strength, limitations, and key points of attention are discussed. Both glass and carbon fibre reinforced polymer (GFRP and CFRP) waste management strategies are critically reviewed. The energy demand and cost of FRP waste disposal routes are also discussed. Landfill and co-incineration are the most common and cheapest techniques to discard FRP scrap. Three main recycling pathways, including mechanical, thermal, and chemical recycling, are reviewed. Chemical recycling is the most energy-intensive and costly route. Mechanical recycling is only suitable for GFRP waste, and it has actually been used at an industrial scale by GFRP manufacturers. Chemical and thermal recycling routes are more appropriate for reclaiming carbon fibres from CFRP, where the value of reclaimed fibres is more than the cost of the recycling process. Discarding FRP waste in a sustainable manner presents a major challenge in a circular economy. With strict legislation on landfill and other environmental limits, recycling, reusing, and repurposing FRP composites will be at the forefront of sustainable waste-management strategies in the future.