Resin Degradation of End-of-Life Wind Turbine Blades to Produce Useful Chemical Compounds in the Context of Waste to Resource Recovery

The selection of proper strategies for degradation and useful product conversion of fiber composites is driven by various environmental and economic factors. Recycling end-of-life (EOL) waste of wind turbine (WT) blade composites is a critical challenge for the renewable energy sector because of its complex composition. The focus of this study is to degrade the complex resins of wind turbine blades to produce useful chemical compounds through the oxy-liquefaction technique under subcritical water conditions. Wind turbine blades have various resins including epoxy resins, glass fibers, and carbon fibers, and they are not easy to separate so the recovery of resin as an individual component is not an easy task. The treatment of selected waste material is carried out at the temperature range of 250 to 350 °C with starting pressure of 20 to 40 bar. The effect of varying weight percentages of oxygen, waste to liquid ratio and residence time on resin degradation has also been studied. Production of various chemical compounds including volatile fatty acids and benzene, toluene and xylene (BTXs) and their dependency on the extent of resin degradation have been checked by using analysis of variance (ANOVA) analysis. Identification of the various chemical compounds against different retention times and temperatures in gas chromatography with flame ionization detection (GC-FID) has also been presented. High resin degradation is an identification of the fact that the oxi-liquefaction technique has the potential to effectively treat the wind turbine blades and support the concept of waste to resource recovery.