Ever gazed at those towering wind turbine blades, silently harnessing the wind’s energy, and wondered about their fate once their operational lifespan ends? These colossal structures, reaching up to 115 meters in length, are crafted from a composite bonded resin fibreglass, presenting both a marvel of engineering and a recycling challenge.
As wind turbine blades approach their approximate 25-year lifespan, wear and tear on their leading edges necessitate replacement. The aging blades, susceptible to noise and friction issues, demand thoughtful consideration for their end-of-life journey. Enter Evashred, engaging in discussions with the Composites Association of New Zealand to revolutionize the recycling process for these immense blades and other composite resin-bonded fiberglass products like boats and fuel storage tanks.
Traditionally, the fate of end-of-life composites involved landfill, burning in kilns used for drying timber or cement, or mechanical recycling for reuse. However, the landfill option is now outdated, and burning raises environmental concerns. Evashred introduces an innovative approach, showcasing a comprehensive flow chart outlining various recycling methods such as combustion, mechanical, thermal, microwave, and solvent.
Evashred’s solution involves breaking down wind turbine blades into a powder form using their primary EV150E shredder. This finely ground fibreglass composite, ranging between 100-150 mesh, is then reused with “chopper guns” in the manufacturing of new composite resin bonded products. The process is intricate and energy-intensive, requiring careful handling due to the combustible nature of the recycled fibreglass powder.
The recycling journey comprises four stages:
Stage 1: Cutting turbine blades into small pieces suitable for the primary EV150E shredder’s infeed hopper.
Stage 2: Utilizing the primary EV150E shredder, housed in a 20-foot shipping container with a hopper roof loading, for primary size reduction.
Stage 3: Achieving secondary size reduction and final sizing inside a 40-foot shipping container, with a target size of 30mm max.
Stage 4: Milling the pre-processed product to a final size of 150 microns or 100 mesh using specialized machines with screens and cyclone dust extraction.
The end result? A recycled fibreglass product, finely powdered and ready for reuse. This material can be seamlessly mixed with virgin fibreglass using a “chopper gun” in the manufacturing process. The applications for this recycled wind turbine blade powder are diverse, but caution is advised due to its highly combustible nature. Every step of the recycling process is meticulously contained within an enclosed environment to ensure safety.
As we witness the chopper gun in action, applying fibreglass to a mould, we witness the culmination of innovation, sustainability, and responsible recycling practices. Evashred’s commitment to redefining the future of wind turbine blade recycling underscores the potential for transformative change in the field of composite fibreglass recycling.