At last year’s COP28 in Dubai, countries agreed to launch the Cement and Concrete Breakthrough initiative, which strives to make near-zero-emission cement production established and growing in every region of the world by 2030. This ambitious goal marks a significant milestone in the global fight against climate change, given that the cement industry is responsible for around 8% of the world’s total CO2 emissions.
Global cement manufacturing produced 1.6 billion metric tonnes of CO2 in 2022, which, if the cement industry were a country, would make it the world’s third or fourth-largest emitter of CO2. With cement being a key ingredient in concrete, and concrete being the second most widely used material after water, addressing these emissions is critical.
A new report released by the World Economic Forum has outlined four main decarboxylation pathways to revolutionize the industry and meet these climate targets.
1. Cutting the Clinker
Clinker, the primary component in cement, is extremely carbon-intensive, making up 90% of overall emissions from cement. Solutions like Limestone Calcined Clay Cement (LC3) show promise in reducing CO2 emissions by around 40% by replacing a significant portion of clinker with less carbon-intensive materials. Scientists at the University of Cambridge have also developed a “zero emissions” technique by reusing cement paste from demolished buildings, potentially saving up to three gigatonnes of CO2 annually.
2. Replacing Limestone
The heating of limestone, which accounts for 50% of emissions in cement production, can be substituted with alternative substances like carbon-free calcium silicate rocks. Companies like Brimstone and Sublime Systems are developing these alternatives, which not only reduce emissions but also capture atmospheric CO2.
3. Fuel Switching and Electrification
Transitioning from fossil fuels to renewable energy sources for heating kilns can significantly cut energy-related emissions. Innovations include electric-based kilns and concentrated solar solutions from companies like CoolBrook, SaltX, Synhelion, and Heliogen.
4. Capturing Carbon
Carbon capture, utilization, and storage (CCUS) could reduce emissions by 36%, according to projections by the Global Cement and Concrete Association. Brevik, Norway, is pioneering this approach with a cement plant integrating a 100-meter-tall CCS facility to trap CO2 from the production process and store it underground securely.
The Cement and Concrete Breakthrough initiative aims for near-zero-emission cement production worldwide by 2030. For this goal to become a reality, the widespread adoption of these innovative processes will be essential. As the world anticipates the transformation of the cement industry, these efforts stand as a beacon of hope, aiming to cement a sustainable future for generations to come.