CARBON CAPTURE CONCRETE Opportunities arise for the concrete industry as it shifts towards sustainability with today’s technological advancements. As the most consumed material in the world researchers are testing the potential of carbon capture, utilisation and storage during cement production to overall reduce the industry’s emissions and turn waste carbon dioxide into a valuable commodity.
Another method to reduce the environmental impact of concrete is carbonation, a naturally occurring process where carbon dioxide from the air is absorbed by the concrete and reacts with calcium hydroxide to form calcium carbonate.
MIT Concrete Sustainability Hub Executive Director Jeremy Gregory sees large market opportunities emerging with the process as concrete mixtures adapt.
However, finding the balance between optimum carbon uptake and minimising the risk of steel rebar corrosion should be considered.
“Many prescriptive requirements limit the ability to improve concrete’s environmental impact — such as limits on the waterto-cement ratio and the use of waste materials in the mixture,” he said in an MIT News interview. Advocating for the use of innovative mixes to lower emissions Gregory states, “Shifting to performance-based specifications is a key technique for encouraging more innovation and meeting cost and environmental impact targets.” According to CarbonCure “This new industry of carbon utilization is expected to become a $1 trillion industry, and reduce global greenhouse gases by up to 15%, by the year 2030.”
ADAA | DECEMBER 2020
08
Gregory says working with academia, industry and the government will contribute to the success and consistent implementation of lower-carbon concrete. From the production of cement to buildings displayed with concrete, the opportunities to create a more sustainable future are increasing. Whether it be by using carbon capture technology at power plants, the use of industrial by-products such as fly ash in cement mixes, or accelerating the carbonisation of concrete in finished applications, the atmosphere and global landscape will benefit.
