Spindles for recycling and dismantling composite materials (wind turbine blades, carbon)
The end of life of composite structures — wind turbine blades in particular — poses an industrial challenge still poorly solved: cutting, dismantling and recovering materials designed to be all but indestructible. The emerging cutting and fibre separation processes rely largely on spindles suited to these atypical materials.
The end-of-life challenge for composite structures
TLDR: Wind turbine blades and many composite structures are designed to withstand decades of extreme mechanical loading — a robustness that becomes a problem when they must be cut up and recycled at end of life, in the absence of a mature industrial recycling chain.
Composite structures, wind turbine blades in particular, are designed to withstand decades of extreme mechanical loading, with glass or carbon fibres embedded in a resin matrix offering unmatched strength and lightness. That robustness, sought in service, becomes a major problem at end of life: the number of wind turbines reaching the end of their contracts is growing fast in Europe, and the industrial chain for recycling these structures is still largely being built. Unlike metals, easily remelted, thermoset composites cannot simply be melted down for reuse — recycling them requires specific processes of cutting, grinding or separating fibres from resin, each with its own requirements in terms of rotating tooling.
Cutting and separation processes that call for specific spindles
TLDR: Dismantling a wind turbine blade or a composite structure requires cutting tools (circular saws, cutters, diamond tools) mounted on spindles able to sustain high cutting forces on abrasive, heterogeneous materials, often in site conditions rather than a controlled workshop.
Dismantling a wind turbine blade or a large composite structure generally relies on cutting tools — circular saws, cutters, diamond tools — mounted on spindles able to sustain high cutting forces against a particularly abrasive and heterogeneous material, where glass or carbon fibres quickly wear down cutting edges. These operations often take place in conditions different from a conventional machining workshop: cutting on site, outdoors, with access and tooling mobility constraints that directly influence the design of the spindles used. Once the structures have been cut into transportable sections, mechanical grinding processes separate the fibres from the resin for recovery — recycling carbon fibres for new composite applications, or energy recovery from the resin — each of these stages relying on rotating equipment sized for this type of material.
What composite recycling demands of the spindle
- Resistance to a highly abrasive material, which quickly wears cutting tools and heavily loads the bearings
- Robustness in on-site cutting conditions, often outdoors and on large structures
- Mechanical endurance under irregular cutting forces, linked to the heterogeneity of the composite material
- Compatibility with different recovery processes (cutting, grinding, fibre separation)
- Reliability in a mobile environment, for equipment deployed directly on the dismantling site
An industrial and environmental challenge still taking shape
Recycling composites, and wind turbine blades in particular, is an industrial and environmental challenge set to grow in the coming years as the European wind fleet ages. This issue informs our thinking on designing spindles suited to atypical materials and working environments — a dimension we also explore through other projects presented in our innovation pages.
Frequently asked questions
Is there already a mature chain for recycling wind turbine blades in France?
The chain is being built, with several pilot projects and technologies under development, but it is not yet fully industrialised at scale.
Is a composite cutting spindle very different from a conventional machining spindle?
The basic principles are similar, but abrasion resistance and endurance in a mobile or outdoor environment call for particular attention in design.
Can Brochexpress design a spindle for a composite cutting or recycling application?
We study this type of project case by case according to your specification — contact us to discuss it.
Brochexpress, watching how the motor spindle evolves
Our engineering office follows technological developments in the sector, including emerging issues linked to recycling composite materials.
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