Mechanisms, technical optimization, and perspectives in the recycling and reprocessing of waste wind turbine blades: A review

Wind energy plays a key role in reducing carbon emissions in the power industry, but current recycling methods for waste wind turbine blades (WTBs) remain unsustainable. This paper reviews the principles, technologies, and potential applications of WTB recycling. It combines fundamental research with an engineering perspective to assess interdependencies across processing stages. Physical methods, such as cutting structural materials and grinding fillers, still face challenges in final waste disposal. Chemical methods, including pyrolysis with product upgrading, solvolysis, and selective deconstruction using liquid-phase catalysts, enable integrated recovery of organic and fiber products but face issues with heat and mass transfer. Moreover, chemical recycling processes must minimize energy consumption, costs, and emissions, while ensuring the separation of chemicals that meet market standards. Additionally, developing deconstruction-functionalization routes to produce higher-value chemicals is crucial. We explore fiber loss mechanisms, mainly due to wear at cutting points, hightemperature hotspots (pyrolysis-oxidation), and chemical reagent-induced leaching of fiber components. We also examine various applications for high-strength and degraded fibers, balancing the integrated recycling of high-value organic products and fibers. Beyond basic research, we discuss the potential of pilot-scale processing equipment and its scalability. In the short term, scalable, cost-effective, and environmentally friendly technologies are essential. In the long term, we recommend developing electrified composite manufacturing and recycling models using locally sourced renewable energy, along with designing new resins for controlled degradation and multi-field coupled deconstruction.