Demonstration of wind turbine rotor Blade Recycling into the Coal Clough Wind Farm decommIssioning Opportunity

PROJECT DESCRIPTION

BACKGROUND

Wind energy is a clean and environmentally friendly source of electricity. Its expansion, however, is creating a growing waste disposal challenge related to the decommissioning of wind turbine (WT) rotor blades. In the very near future when the first wind farms start to be dismantled or repowered, the question will be what to do with such complex waste streams. LIFE-BRIO aimed to provide a sustainable, integral solution to this problem. While most parts of wind turbines (foundation, tower, drive train, generator or electronics) are made of materials and components (concrete, steel, iron, copper etc.) with well-known recovery routes, the WT rotor blades are made of complex structures and materials, and consequently the preparation of waste and its recycling represents a challenge.

OBJECTIVES

The main objective of the LIFE-BRIO project was to demonstrate from a lifecycle perspective an innovative and sustainable methodology for end-of-life WT blades management and recycling. This scheme would allow valuable inorganic fibres and other materials to be recovered and reused as reinforcement in cement-based products and as cores in functionalised multilayer structures. An integral approach would be used, considering all the stages involved in the process: the dismantling of the rotor blades in the wind farm, the whole recycling process for material resources recovery, and their incorporation in new products. This alternative approach would avoid the adverse impact on the environment of incineration or disposal in landfills.

Specific project aims were to:

demonstrate upgraded mechanical recycling processes guaranteeing an optimised recovery of fibres from the composite materials of the WT blades;

foster closed loop recycling by incorporating the recovered fibres into precast concrete elements such as manholes, containment systems and paving;

develop policy and legislative recommendations for the EU for management and recycling of end-of-life WT blades;

anticipate feasible solutions for the management of emerging complex waste streams;

set the basis for an economic and environmental procedure guaranteeing an upgraded recovery of fibres and other materials;

assess optimised reverse logistic schemes for the management of discarded WT blades into the Coal Clough windfarm decommissioning phase;

perform a Life Cycle Assessment of the whole process;

promote local networks associated with the reverse supply chain of WT blades; and

disseminate the project results to target groups.

RESULTS

The LIFE-BRIO project demonstrated from a life cycle perspective an innovative and sustainable methodology for end-of-life WT blades management and recycling. It was carried out during the decommissioning of the rotor blades at the Coal Clough wind farm in the UK. The mechanical recycling process applied on a pilot scale and the applications selected for the recycled materials provide high recovery rates of this waste stream. The project showed that almost all the blade material can be recycled mechanically to obtain fractions of materials, all of them with possibilities for reintroduction in the economic cycle, and the potential rejections from the process are irrelevant.

The concentration process performed provided fractions of metals (5.6%) for smelting, glass fibres (43.9%) to be recycled as reinforcement in concrete precast elements and ground materials, and short fibres, inorganic fillers and polymers (50.5%) to be recycled as cores of multilayer panels. Additionally, three types of precast concrete products were developed for the integration of the fibres (homogeneous fraction) recovered from wind turbine blades. The obtained prototypes were inspected, tested and installed in real life conditions. Observations and results obtained from tests validate the use of the recycled fibres in concrete precast elements. The use of the fibres moreover can slightly reduce the use of other materials (cement and aggregates) and it does not affect the manufacturing process. The fibres recovered from WT blades recycling can improve the performance of precast concrete products.

Two types of multilayer panels (thermoset and thermoplastic nature) with cores made of recovered materials coming from the mechanical recycling of rotor blades were manufactured and tested. The technical performance of the multilayer panels is closely related to the type of outer peels. Non-fibrous fraction can also be used as an efficient core material in sandwich panels.

The project contributed to the Waste Framework Directive, the Landfill of Waste Directive and the Incineration of Waste Directive that promote recycling prior to landfilling or incineration.

However, the project offers guidelines for more specific regulation for the wind energy industry. The project helped increase awareness of this renewable energy among the general public, and contributed to the promotion of the use of wind energy. Furthermore, the proposed solution will save costs associated with the disposal of material in landfills and incineration (normally, cement plants and other energy power installations charge a fee to accept waste as an alternative fuel).

Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).