On yearly basis in Finland, concrete buildings and recycled concrete absorb about 23% of the CO2 emissions of the cement industry. For concrete to be carbon neutral, active measures are also needed.
One of the most recent and interesting emission reduction technologies in the sector is the curing of the concrete with carbon dioxide captured from industrial emissions (CCU).
In carbon dioxide curing, benefits arise in two ways: captured carbon dioxide is utilized and bound to concrete, and concrete has been reported becoming stronger when introduced to carbon dioxide. Thanks to CO2 curing, the amount of emission-intensive cement can be reduced when making concrete.
Carbon dioxide curing of concrete has been studied primarily by exposing hardening concrete to CO2 under high pressure. However, technology is not suitable for large elements and cannot be used in the production of ready-mix concrete. Concrete as a carbon sink – solutions for low-carbon construction (BEHI) project is studying the CO2 curing of concrete while it is still in a plastic phase.
The main objective of the project is to promote the carbon neutrality of concrete through the research and development of CO2 curing for the large-scale use of the concrete industry. During the project, the use and demands of the CO2 will be investigated, validated and tested. It will be optimized so that the characteristics of concrete are not weakened. Cases of usage are piloted in real life operating environment.
Verified knowledge of the performance technology, carbon footprint and technical economic advantages and limitations of CO2 mixing are the main results of the project.