Raw-crushed wind-turbine blade: Waste characterization and suitability for use in concrete production

Many of the first wind-turbine installations are reaching the end of their useful life, so their blades have to be replaced. Inexpensive, sustainable, and straightforward recycling solutions are therefore needed. The conversion of turbine blades into raw materials for concrete solutions is proposed in this paper, through a novel recycling process entailing non-selective cutting, crushing, and sieving of the blade walls, without component separation. The material, Raw-Crushed Wind-Turbine Blade (RCWTB), consists of fiberglass-composite fibers, polyurethane, and balsa-wood particles. It serves as concrete fibers and aggregates, according to its physical and microscopic characterizations. A customized concrete mix design and a five-stage mixing procedure with up to 6% RCWTB achieved suitable workability levels. The compressive strength of the RCWTB concrete was 40 MPa, and it had a higher load-bearing capacity and a lower carbon footprint than ordinary concrete. The results encourage research on the overall performance of RCWTB concretes.