Gdansk University of Technology researchers look for ways to recycle used wind turbine blades
An interdepartmental research team from the Gdansk University of Technology is looking for ways to recycle worn-out wind turbine blades in an energy-efficient way. The researchers hope that the solutions developed will help protect the environment and increase the availability of building materials.
A research team from the Faculty of Civil and Environmental Engineering and the Faculty of Architecture, led by Professor Magdalena Rucka, will develop a system for managing decommissioned wind turbine blades for re-use in construction and architecture, the press office of the Gdansk technical university announced in a press release.
Wind turbine blades are mostly made of polymer composite material.
– They are mainly layered structures, consisting of glass and carbon fabrics and resin, explained Prof Rucka, head of the project – and of the PG Department of Materials Strength, as quoted in the release.
She pointed out that, thanks to their high fibre content, the turbine blades have a very high strength-to-weight ratio and excellent load-bearing capacity and durability. At the same time, she stressed, these characteristics make them difficult to recycle.
The release stated that the blades are designed to last an average of 20-25 years, and once they are decommissioned, they must be disposed of.
– Currently, this is mostly done by landfill or by recycling using mechanical, thermal or chemical methods, Prof Rucka said.
In her opinion, “many of these approaches are energy-intensive and environmentally unfriendly”.
– ‘In our project, we want to propose a comprehensive approach to blade recycling with the lowest possible energy intensity compared to current methods, which will take advantage of the high load-bearing capacity of the blade and, as a result, contribute to reducing current problems in construction, including those related to the limited availability of certain materials,’ the project manager assessed.
The project has been divided into three parallel parts, in which the research teams will develop methodologies for several shovel reuse options.
The first part of the project will be carried out by architects. It will be led by Dr Monika Zielińska, who has announced an open architectural competition for a concept for the use of the shovel in various elements of small architecture, including – a shelter for bicycles that could be erected on the campus.
In the second part, under the direction of Dr Mikołaj Miśkiewicz, Prof. PG, researchers will assess the possibilities of using shovel fragments as load-bearing elements in building and infrastructure applications. Among other things, a concept for a pedestrian bridge girder will be developed.
Prof Miśkiewicz, quoted in the release, said that there are currently no systematised types of wind turbine blades, and each is an independent structure and can have different applications.
– We plan to develop a methodology for dealing with them, he pointed out.
He added that, as a first step, the researchers will assess the condition of the harvested blades after they have been used on wind farms. “If all or most of the blade can be used for structural applications, taking into account any damage and delamination of the material, we will be able to make structural components and landscaping elements,” – he stressed.
The scientists also mention all kinds of roofing, including walkways, fences, climbing walls and foundation structures, among others, as potential applications for larger fragments of the material.
– If the condition of the shovel that we get into processing does not allow it to be used in this way – we have identified courses of action that will allow us to grind the shovel and use it as aggregate,’ said Prof Miśkiewicz.
The third part of the project, carried out under the direction of Dr Marzena Kurpinska, will assess the possibility of using the ground parts of the shovel as an aggregate replacement for concrete. The researchers estimate that ground shovels could account for up to 40 per cent of the volume of natural aggregate used to produce the concrete mix used in engineering structures, maintaining the strength properties and durability of the concrete.
Dr Kurpinska, quoted in the release, stressed that the extraction of natural aggregates and the method of refining them by washing and crushing them in such a way that they are suitable for concrete production requires a large amount of energy.
– In addition, some regions have problems with the availability of certain fractions of aggregate, she noted.
She added that the researchers see the possibility of replacing some of the aggregates with that from recycled shovels. “The preliminary studies we have conducted are promising. We still have time-consuming durability studies ahead of us to determine the usefulness of such a modified cement composite,” – she explained.