This problem is being worked on. I recently listened to this podcast which outlines two approaches to low carbon concrete - https://www.npr.org/transcripts/923966126
Take away points:
* The first approach is to use a different mix that can nearly half the temperature required to produce the concrete. This can reduce the CO2 emissions to produce the concrete by up to 40%
* The second approach uses pure CO2 to cure the concrete which locks away more CO2 in the concrete
* The concrete produced by these approaches need to be fully tested before the methods can be rolled out and costs reduced
Take away points:
* The first approach is to use a different mix that can nearly half the temperature required to produce the concrete. This can reduce the CO2 emissions to produce the concrete by up to 40%
* The second approach uses pure CO2 to cure the concrete which locks away more CO2 in the concrete
* The concrete produced by these approaches need to be fully tested before the methods can be rolled out and costs reduced