I have windmills in the picture again. While you may think this fairly Don Quixotic of me, it really is not. Wind turbine blades, as I have said many times in this blog, are now the highest tonnage application of advanced composites worldwide. And that is not going to change any time soon because of the proliferation of wind energy systems all over the planet, and especially offshore where you can build very large ones. That pic is in fact from the Blog post from EuCIA that is effectively a treatise on what is required to complete the sustainability cycle for composite materials.
So, yes, I am going to talk about sustainability again. Mostly because this is a topic I care about deeply, but also because this is the direction that the industry is taking. The new concept that is taking hold – at least in Europe – is “Design for Sustainability.” But what does this actually mean? That is the question that needs to be asked and that needs to be asked repeatedly.
Design for Sustainability means different things to different people – as usual.
To the raw material suppliers this just means making their product out of sustainable materials – like using the wood byproduct lignin to make fibers like I talked about last week. Or a resin manufacturer formulating resins using plant-based precursors rather than petroleum. Or a composites designer using only natural, plant based fibers and resins in a design.
But real sustainability is much more than that. Real sustainability includes the entire life cycle of the materials.
This includes where the materials came from, how they were processed into usable fibers and resins, how those fibers and resins were made into a composite part, and finally what was done when the part came to the end of its use and was recycled back to raw materials and made into another part.
This is, of course, the holy grail if you will of the sustainability of composites. And, as I mentioned above, the Europeans are quite a bit ahead of us here in the US. The European Composites Industry Association (EuCIA - https://eucia.eu/) has an ongoing program to develop the technologies for a circular composite materials economy. If you look at the upper right pic above, you will see the entirety of the idea. It starts at the top with raw materials extraction, goes to material processing, then part manufacturing, then assembly, use, end of life, and finally goes back to being raw material – only to close this cycle completely we need to eventually phase out raw materials extraction from other than sustainable materials, and the recycled waste stream needs to be a large percentage of that raw material input to this circular process.
So, what is actually required to complete the cycle? There are of course several aspects to this and technologies that need to be either developed or matured to the point that they are economically feasible. The bottom right picture above is just one of these. It is from the organization I talked about last week that uses nanomaterials on the surface of carbon fibers to make them inherently recyclable. This figure was extracted from an article in the Journal of Composites Science (Koumoulos, E.P.; Trompeta, A.-F.; Santos, R.-M.; Martins, M.; Santos, C.M.d.; Iglesias, V.; Böhm, R.; Gong, G.; Chiminelli, A.; Verpoest, I.; Kiekens, P.; Charitidis, C.A. Research and Development in Carbon Fibers and Advanced High-Performance Composites Supply Chain in Europe: A Roadmap for Challenges and the Industrial Uptake. J. Compos. Sci. 2019, 3, 86. https://doi.org/10.3390/jcs3030086) from researchers in Europe that are actively seeking ways to make carbon fiber easily recyclable at a part’s end of use.
This is, of course, only the start of development of technologies to complete the sustainability cycle for composites and to make it economically attractive enough that it becomes the norm in the use of composite materials.
I’m going to come back to this topic soon and complete the cycle for everyone because there is a lot to write about and this is a very important topic in the industry and is going to become the future of the composites industry. If you can’t tell I’m somewhat of an optimist, but I am also a realist. The economics of re-use of composites rather than deriving them from petroleum sources already has made sense to nearly everyone in the industry, so my optimism I believe is shared worldwide.
Commentaires