The “Concrete Sustainability, Science and Solutions” (C3S) research group at the Polytechnic University of Catalonia (UPC) is conducting tests to replace part of the natural sand in concrete with Carboliva biochar. Their initial results are satisfactory, as the mixture shows promising mechanical performance and greater resistance to water ingress, suggesting that biochar can help create more sustainable mixtures.
Furthermore, it must be noted that for every ton of biochar incorporated, a significant amount of CO2 is captured that would otherwise return to the atmosphere if the biomass were to decompose or be burned.
The work of the C3S Research Group demonstrates that materials science can go hand in hand with ecology. The use of agricultural by-products is not just a “green” alternative, but a viable technical strategy to create more resilient cities with a lower environmental impact by supporting a lower-impact construction sector.
The biochar used in the research, as previously indicated, is made from olive stones by Carboliva. The company transforms this residue from olive milling through a controlled pyrolysis process in the absence of oxygen, which prevents the carbon in the stone from turning into CO2 and being released into the atmosphere; instead, the carbon is “fixed” into a solid and stable structure. By integrating biochar into concrete, buildings would become a carbon sink. The CO2 that the olive tree absorbed during its life would remain trapped in the structure of the built element.
Alvaro Espuny, CEO of Carboliva, highlights that this research demonstrates that Biochar is a good resource for decarbonizing materials and processes without making major changes or incurring large investments. “If we take into account that concrete is the second most consumed material in the world after water, the incorporation of biochar to build the buildings of the future would represent a major breakthrough in sustainability,” he asserts, noting that biochar is a very promising path to achieving emission-free construction and that, for this very reason, Carboliva promotes R lines in both concrete and asphalt mixtures.
