Cement is the glue that, when mixed with sand, aggregate, and water, produces concrete. Many aspects of modern civilization are made possible because of concrete, an indispensable material that is one of the most used substances on earth. Demand for cement and concrete is likely to continue to increase due to the expanding need for infrastructure construction, including to provide a strong foundation to withstand the severe weather events that are predicted due to changes in climate.
How Do We Decarbonize Cement Manufacturing?
Ninety percent of emissions from cement making are from the kiln where limestone and silica (shale and sand) are heated to high temperatures (~1450°C) to chemically create the material, called clinker, necessary in making cement. Sixty percent of the on-site emissions associated with this step are process emissions–coming from the chemical decomposition of limestone (CaCO3 –> CaO + CO2) in the kiln. The rest come from the combustion of fossil fuels to reach the high temperatures required for the process.
To help tackle the challenge of decarbonizing the cement industry, research and development (R&D) is needed across the following areas:
- Next-generation cement/concrete formulations and production routes
- Low-carbon fuels
- Carbon-capture technologies.