As wind energy continues to surge as one of the leading renewable energy sources globally, the disposal of wind turbine blades has emerged as a pressing environmental challenge. Lithuanian researchers have stepped up to the plate with a groundbreaking solution, leveraging the benefits of pyrolysis to tackle pollution and pave the way for sustainable recycling.
Wind turbine blades, crucial components in the renewable energy landscape, typically have operational lifespans of 20 to 25 years. However, their composite construction—featuring layers of fibreglass or carbon fibre reinforced with epoxy or polyester resin—poses significant hurdles to recycling.
Traditionally, wind turbine blades were nearly impossible to recycle, leading to environmentally risky disposal methods like landfilling. Recognizing the urgent need for innovative solutions, researchers worldwide have been on the hunt for sustainable alternatives.
In 2022, Dr. Samy Yousef and a team of researchers from Kaunas University of Technology (KTU) Faculty of Mechanical Engineering and Design, along with collaborators from the Lithuanian Energy Institute, embarked on a series of experiments to revolutionize wind turbine blade recycling.
Their approach focused on utilizing pyrolysis—a process that breaks down materials at high temperatures in the absence of oxygen—aided by a specialized catalyst. By subjecting old composite materials, including glass fibre-reinforced epoxy resin composites, to pyrolysis, the researchers aimed to extract valuable components for reuse while converting the remaining material into energy.
While initial experiments provided valuable insights, limitations in sample availability hindered progress. In 2023, the team obtained real wind turbine blade fragments from Danish company “European Energy A/S,” enabling more comprehensive research.
Analysis of the blade fragments revealed the prevalence of unsaturated polyester resins, particularly in the Baltic region, due to their cost-effectiveness. However, the main component of these resins, styrene, poses significant environmental and health risks when improperly disposed of.
To mitigate these risks, the research team successfully extracted styrene from the blades in the form of styrene-rich oil using the pyrolysis process. This innovative approach not only addresses the challenge of disposing of toxic and non-biodegradable materials but also offers opportunities for sustainable reuse.
Moreover, through subsequent processes, the team recovered and purified fibres and carbon, providing a sustainable filler material to enhance the mechanical properties of composite materials.
Despite these advancements, Dr. Yousef acknowledges environmental challenges associated with post-treatment processes such as washing and oxidation. Nonetheless, the research marks a significant step forward in sustainable wind turbine blade recycling, with life cycle assessments revealing promising environmental benefits compared to landfill disposal.
While work continues to improve the recycling process, the potential for transforming waste into worth underscores the importance of innovative solutions in the transition to a more sustainable future.
Source
Recovery of energy and carbon fibre from wind turbine blades waste (carbon fibre/unsaturated polyester resin) using pyrolysis process and its life-cycle assessment, Environmental Research, ScienceDirect, 2024-03
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