Lithuania – Researchers from Kaunas University of Technology (KTU) and the Lithuanian Energy Institute (LEI) have proposed a method for recycling wind turbine blades.
Phosphate and fibre were separated from the composite materials using pyrolysis. Science says the extracted materials can be reused, and the process is almost waste-free, according to them.
Glass fiber-reinforced polymer laminate composite wind turbine blades can last up to 25 years. GFRP is notoriously difficult to decompose after it’s been disposed of in landfills. The renewable energy sector now faces a significant obstacle in this regard.
Wind turbine blades are thought to be responsible for 10% of Europe’s waste of fiber-reinforced composite material. Wind turbine blade waste is expected to rise to around two million tonnes by the year 2050, according to a new study. Many countries have banned the disposal of composite materials in landfills, making the recycling of used wind turbine blades a difficult problem to solve.
Dr. Yousef’s research team has conducted several experiments involving the breakdown of GFRP into its component parts in an effort to meet this challenge.
Conversion without waste
GFRP composites are used in a wide range of industries, including automobile manufacturing, maritime vessels, oil and gas production, construction, sporting goods, and more. The global demand for GFRP is increasing at a rate of six percent per year in the aerospace, wind energy, and electronics industries.
Pyrolysis was applied to different batches of fiberglass thermoset and fiberglass thermoplastic composites to measure the extraction of phenol (the primary component in the production of phenolic resins and the manufacture of nylon) in each case during the experiments. As a result, each batch’s basic raw materials were scrutinized. Adding additive nanoparticles (such as carbon black) can reduce the yield of useful components, which the researchers investigated.
Pyrolysis yield varies depending on temperature, but the proximate measurement showed that in all cases the numerous volatile compounds (up to 66%) and fiber residue (around 30%) were extracted. Additions of carbon nanotubes and graphene fiber nanoparticles resulted in a significant increase in phenol production.
Using actual blades
Instead of using actual wind turbine blades, the researchers used samples prepared in a lab with compositions similar to those used in the manufacture of wind turbine blades. The research team is currently developing a model that can be used to scale and calculate the wider economic and environmental impact of the findings.
As part of a larger research effort, this study examines the practical implementation of circular economy principles.