Recovery of glass fiber from retired wind turbine blades based on low-temperature plasma assisted flotation

Retired wind turbine blades have emerged as a fast-growing non-hazardous industrial solid waste globally, with the retirement peak approaching and around 43 million tons of related waste expected by 2050. Conventional disposal methods (landfilling, incineration) pose severe environmental risks (e.g., toxic leakage, carbon emissions) and waste valuable glass fiber resources, challenging sustainable solid waste management. To address this, this study proposed a process integrating impact crushing, low-temperature plasma (LTP) treatment, and flotation. Key optimized performance: 95% of the < 0.25 mm fraction achieved effective liberation of glass fiber from resin within 120 s without fiber breakage; LTP treatment (100 W, 16 h, 0.2 L/min O₂) oxidized the 0-30 nm residual resin to CO₂/H₂O, reducing surface carbon content from 62.0 wt% to 1.0 wt% while maintaining fiber strength; two-stage flotation (800 rpm, 0.1 m³/h aeration) with sodium hexametaphosphate (20 kg/t), dodecylamine (2 kg/t), and sec-octanol (740 g/t) obtained clean glass fiber with 78.4 wt% purity and 48.0% recovery. This green, scalable route addresses critical solid waste management challenges, promotes circular economy, and is transferable to other composite-based industrial wastes, providing practical value for managers and policymakers.