Process optimization and economic estimation of nitric acid dissolution for recycling waste wind blades

Abstract

With the widespread retirement of wind turbines, many discarded waste wind blades have been generated, and how to handle them efficiently has become a critical issue. This study investigated the dissolution of discarded waste wind blades with nitric acid (HNO₃) by varying acid concentration, reaction time, temperature, and HNO₃ volume. Based on a series of single-factor experiments, the optimal conditions for low energy and acid consumption were determined, and the separation rate of resin reached 95%. As the cost-benefit analysis results suggested, an economic method to recycle a variety of high-value products was achieved. Furthermore, the implementation of a continuous chemical decomposition strategy for multi-batch processing significantly minimized acid consumption, resulting in a further reduction in recycling costs. This work provided an economically and technologically feasible way for recycling materials from decommissioned wind turbines, in order to answer the challenge of emerging solid waste management.