Concrete and the process of Recarbonation
Concrete can absorb CO2 from the atmosphere over its lifetime, in a process known as recarbonation.
Recarbonation is a natural process, occurring when concrete reacts with CO2 in the air.
This process of Recarbonation occurs when concrete reacts with CO2 in the atmosphere and the actual amount of carbonation will depend on a range of parameters. A conservative estimate of the cement carbonation sink provided by all concrete is 20% of the process CO2 emissions released during cement production.
The United Nations (UN) has acknowledged that the process of recarbonation over the lifecycle of concrete elements absorbs a proportion of the process CO2 emissions released during cement production, and estimates that approximately 200 million tonnes of carbon are absorbed worldwide annually by this “cement carbonation sink”.[2,3]