Making cement the conventional way generates about 9% of global CO₂ emissions. This project aims to break that link by turning old concrete and waste CO₂ into a new cement that contains almost no Portland cement clinker—the carbon-intensive ingredient in standard cement. Current research has focused mostly on capturing and storing CO₂ from cement plants, but has largely ignored the possibility of using that captured CO₂ to make new cement. CO24Cem fills that gap by chemically modifying waste cement paste, optimising the carbonation reactor conditions, and testing novel material combinations to create a cement that is reactive enough to replace clinker entirely. If the team succeeds, European cement production could become nearly carbon-free, and the industry could recycle close to 100% of its non-energy materials. The technology is designed to scale globally to multiple gigatonnes of concrete per year. The project will also produce demonstration concrete products and run a full life-cycle assessment to confirm the environmental benefits. This is a direct engineering and chemistry challenge—not fundamental science—aimed at one of the hardest sectors to decarbonise in the fight against 1.5–2°C global warming.
View original technical description
Decarbonising concrete production is important since it is directly responsible for ~9% of global CO2 emissions. Academic research in low carbon concrete has overwhelmingly focused on a limited set of supply-side decarbonisation measures, such as carbon capture and storage, broadly overlooking the huge potential of carbon capture and utilisation. CO24Cem will address this knowledge gap and decarbonisation goal by delivering a near-zero CO2 emissions cement produced by carbonating end-of-life concrete with waste CO2. The main scientific aim in CO24Cem is to create this carbonated cement with sufficiently high reactivity so it contains ~0% Portland cement clinker, which is the high-CO2 material produced in cement plants. This aim will be achieved by making breakthrough advancements in cement chemistry and carbonation process technology, which will involve chemical modification of the carbonation reactor feedstock (end-of-life cement paste), optimisation of the carbonation reactor conditions, and the use of novel combinations of materials in its mix design. Success here will create an important pathway to completely decarbonise European cement production and achieve ~100% recycling of non-energy materials in this industry. The breakthrough cement technology will also have excellent use potential globally at the multiple gigaton scale. In CO24Cem, near-zero CO2 emissions concrete products will be produced using this breakthrough technology, accompanied by a life cycle assessment study, to demonstrate its feasibility and the massive potential beneficial impacts. Overall, CO24Cem represents a significant step towards decarbonising the cement and concrete industries, which is one of the most difficult to achieve yet essential aspects of 1.5-2 C temperature rise climate change mitigation targets.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know