Carbon dioxide uptake into concrete

Over the last 20 years research has explored CO2 uptake in cement during its service life which has promoted a change in the inclusion of this process in global carbon budgets. Some suggest that as much as 200 MtC (720 Mt CO2) yr-1 is taken up by existing concrete structures. A figure that has been included in the latest report from the IPCC, and is equivalent to about one half of the calcination emissions from current cement production.

The model that underpins this has a fundamental weakness in that it considers CO2 diffusion into the material, not its reaction with the cement. As such, work is needed to refine the model with data on CO2 cement reaction. Such a project could be the development of a numerical model that simulates CO2 reaction in concrete, or experimental work to underpin such model development.