End of Life Wind Turbine Blade Recycling : Challenges From an Environmental, Economic and Practical Viewpoint

Sammanfattning

The goal of the European Union is to make strides towards a circular economy. This means recycling or re-using as much of the material in the economic system as possible. The wind industry faces a great challenge in the years to come as huge quantities of increasingly larger wind turbines reach the end of their service-life. When old wind turbines have been decommissioned, most parts are scrapped and recycled into other applications. The turbineblades however are made from glass- and carbon fibre polymers and are not as easily recycled. Recent bans of putting the blades into landfills steer the industry toward finding new applicationfor the old wind turbine blades. Re-purposing the blades as bridges, shelters, houses and towers has been suggested, as well as re-cycle the material or recover the blades as energy. Regardless of what method is preferred, the wind turbine blades need to be transported to a re-purpose or recycling facility. Because of the distribution of wind turbines within countries, the optimal location of such facilities can be hard to evaluate. The centre-of-gravity method (evaluating the centre-of-mass) has been suggested as a way of evaluating the optimal location of such facilities. The method is built upon the assumption that the wind turbine blade can be easily downsized, transported and accommodated in a single transport. In order to achieve this, the present thesis has compared and evaluated different methods of segmenting the wind turbine blade (mechanical, thermal and chemical) as well as different loading and compressing methods. The mechanical separation methods tend to be more suitable than the thermal and chemical counterparts. The choice of loading methods is dictated by the resulting fraction size of the wind turbine blade after separation. The mass density of the resulting blade could be increased with a suitable way of compression (hydraulic or gravity).