Cement coprocessing: a win-win solution for end-of-life composites

Before continuing, read the Part 1 of this article.

In June 2023, seven associations [1], representing a large part of the composites value chain, agreed that cement coprocessing offers a sustainable recycling solution, using 100% of end-of-life composite materials that can immediately be deployed at large scale and which is different from other promising composite recycling technologies that have not reached yet technical and/or economical readiness.

A sustainable and circular solution for end-of-life composites

The cement coprocessing of end-of-life composite materials allows material use, by reducing the amount of natural raw materials in cement manufacturing, while mitigating climate change contributions through replacement of fossil energy sources. As the cement in concrete can be fully recycled and used to make new concrete, cement coprocessing is also a circular solution for the end-of-life composite materials. This is a win-win solution that:

• allows for a sustainable solution for end-of-life composite materials from decommissioned assets, energy, marine, transportation and composites manufacturing processes;
• supports sustainable developments and European decarbonisation goals;
• increases the overall circularity of end-of-life composite materials.

A life cycle contribution of composites close-up

Composites are durable, engineered materials. They are characterised by long service life, high mechanical strength, excellent chemical and heat resistance properties. Freedom of design allows a wide range of end use applications. Thanks to those exceptional properties, composites deliver significant material and energy savings, helping to achieve today’s energy and climate goals, including the European Green Deal agenda.

Composite materials are widely used in the energy sector. They are the material of choice for lightweight, durable solutions in transportation and infrastructure, contributing to reducing energy use in these sectors. It is expected that their use in several segments will grow significantly which also means that, at some point in time, the amount of end of use material will grow.

To accelerate the circularity of composites materials, large industrial segments made recent commitments. WindEurope, representing the European wind turbine manufacturers, has called for a Europe-wide landfill ban on decommissioned wind turbine blades by 2025. The European Boating Industry (EBI) has recently launched its “Roadmap on the implementation of the circular economy for end-of-life boats”, in which it commits to phase out landfilling and energy recovery by 2030.

Cement industry’s contribution

Cement and concrete materials play an essential role to help Europe achieving its strategic objectives on growth, innovation, social inclusion; as well as climate and energy ones for its use in houses, industrial facilities, office buildings and infrastructure. More importantly, cement and concrete are pivotal to building a climate neutral Europe. Foundations of wind turbines, hydro-electric dams, passive housing, tidal power installations, and new transport and maritime infrastructure, all rely on the unique qualities of concrete. Cement production is energy intensive and has a historically high carbon footprint. Fundamental for the cement industry’s operations is the quality of the product (cement) in combination with the environmental impact.

According to CEMBUREAU’s Carbon Neutrality Roadmap, by 2050, the European cement sector pledges to become climate neutral. The cement sector also committed to an intermediate 2030 target to reduce the carbon footprint by almost 40% to an average 0.47 t CO₂ per ton of cement. Recycling of end-of-life composite materials through cement coprocessing will contribute reaching this goal.

The updated life cycle analysis (LCA) of cement coprocessing is under preparation by a platform of stakeholders [2]. It will further substantiate the quantification of the environmental advantages of cement coprocessing.

Composites are circular materials

In a recent study by the Joint Research Centre (JRC) [3], the importance of substituting materials is highlighted as well as the longevity of use. The already long life of composites (often 25 to 50+ years) is further extended by using it to make concrete with the potential another life for more than 100 years, following again another reuse opportunity.

With EuCIA, estimating that 40% to 70% of the end-of-life composite materials today still end up in landfills or is incinerated without energy recovery, this is an enormous opportunity. In comparison, the amount of end-of-life of composite materials is relatively small with other waste streams, as mentionned volumes are rapidly increasing, and the need for waste management solutions, in line with the circular economy model, is becoming more and more urgent.

Composites have a great potential to be circularly used, be it in closed loop applications, preserving the intrinsic functionality such as making new composite parts from processed composites, be it in open loop processes where the primary function is not required (“non-functional”), but the constituents are fully applied as in coprocessing. The future is promising from a technical point of view. However, there are other barriers that need to be overcome.

Need for a regulatory framework

Our industries stand united in promoting the coprocessing of end-of-life composite materials in cement clinker production as well as other opportunities for circular use. However, a strong supporting regulatory framework is necessary in order to overcome the barriers preventing scale-up coprocessing end-of-life composite materials as well as other applications. These include a lack of visibility on the relevant waste stream. They now fall under various waste streams including construction and demolition waste, and a subsequent lack of a stable and consistent supply of end-of-life composite materials. Both are essential to ensure a reliable and constant flow of secondary materials specific to circular reuse. We, therefore, call on European policymakers to:

• recognise coprocessing as a circular process according to the Waste Framework Directive 2008/98/EC for its raw material recyclability;
• develop an EU-wide harmonised model for a separate waste collection scheme for end-of-life composite materials to simplify waste management, improve efficiency of resource flows, and ensure better access to secondary materials for the cement industry;
• establish dedicated waste codes for end-of-life composite materials. This is an essential pre-requirement to improve visibility of and access to the relevant waste streams (including volumes and location) and attract investments;
• phase out the landfilling of end-of-life composite materials from the wind energy and boating sectors, and promote the development of sustainable recycling alternatives for all composite materials.

Coprocessing as well as technologies in development are very well suited to process end-of-life composites materials. There is a need to overcome some barriers as to the acceptance of cement coprocessing as an excellent open loop solution, effectively using the intrinsic material value of composites. The industry looks for cooperation by policymakers to level barriers that currently prevent the optimal reuse.

References:
[1] eucia.eu/wp-content/uploads/2023/07/230623-Joint-position-Co-processing-Composites.pdf
[2] www.avk-tv.de/files/20130212_recycling_made_easy.pdf
[3] publications.jrc.ec.europa.eu/repository/handle/JRC131531