This article speaks about the role of decarbonization in fields such as construction. Concrete is normally a very carbon and energy intensive material to make. The production of the compound known as clinker is especially energy intensive.
“Clinker is a nodular material which is used as the binder in cement products. Cement is a binding agent that sets and hardens to adhere to building units such as stones, bricks, tiles etc.” (Hasan, n.d).
Thus, a way must be found to either eliminate this material completely or produce it in a more sustainable way. Concrete manufacturing is currently responsible for around 7% of total global carbon dioxide emissions (Gillis et al., 2023). There is a way of decarbonizing this industry. If clinker is still to be used, renewable energies must be used in order to produce it. Alternative substitutes could be used. A study was conducted to analyze the strength of using other clinker alternatives. “Combined use of calcined clay and limestone can be used at much lower levels of clinker than calcined clay alone without reduction in mechanical properties” (Joseph et al., 2023). Thus, in parts of the world where calcined clay is found, it should absolutely be used as an alternative to clinker.
Used coffee grounds are being substituted for sand in the manufacturing processes. In using coffee grounds, a sturdier concrete mixture can be created, as well as reducing the amount of coffee grounds that end up on landfills (Klein, 2023). A researcher at RMIT University in Melbourne discovered that by adding coffee grounds the mixture is 29% stronger than concrete (Klein, 2023).
The good news is that we can see that there are many theoretical ways of integrating techniques to decarbonize the industry. One of them is combining carbon capture facilities within cement plants, as well as using substitutes for traditional materials used in the production of concrete (Gillis et al., 2023). However, a major obstacle remains in the way of making other types of concrete attractive. Namely, the so-called Ordinary Portland Cement (OPC), the industry standard. It is engrained into “virtually every building code on the planet” (Gillis et al., 2023). This is a huge hurdle to overcome and there must be a shift away from this standard, in order for the industry to have a chance of move towards decarbonization.
P.S. Do you know about so-called self-healing concrete?
Reference:
Gillis, N. (2023). How to decarbonize concrete and build a better future. GreenBiz. https://www.greenbiz.com/article/how-decarbonize-concrete-and-build-better-future
Hasan, S. T. (n.d.). Syeda Tahsin Hasan. Civil Engineering. https://civiltoday.com/civil-engineering-materials/cement/109-difference-between-clinker-and-cement
Joseph, S., Dhandapani, Y., Geddes, D. A., Zhao, Z., Bishnoi, S., Vieira, M., Martirena, F., Castel, A., Kanavaris, F., Bansal, T., & Riding, K. A. (2023, April 26). Mechanical properties of concrete made with calcined clay: A review by Rilem TC-282 CCL – Materials and Structures. SpringerLink. https://link.springer.com/article/10.1617/s11527-023-02118-8
Klein, A. (2023, August 22). Recycled coffee grounds can be used to make stronger concrete. New Scientist. https://www.newscientist.com/article/2388570-recycled-coffee-grounds-can-be-used-to-make-stronger-concrete/
Self-healing concrete. GCCA. (2021, April 30). https://gccassociation.org/essential-concrete/self-healing-concrete/