CDW as a carbon dioxide sink and new material for production

Swedish construction sector is facing a great challenge related to CO2 emissions accounting for 21% of the total CO2 emissions in Sweden. The growing construction and infrastructure development demands ca 100 million tons of construction material per year.

Sweden produces 2 million tons of concrete waste per year which is used in low value un-bound applications in road construction, followed by landfilling leaving a very small proportion for the production of new concrete.

Using crushed demolition waste as carbonation sink and as aggregates extends the technical life of the original material and as a potential CCS/CCU.

The challenge is technical: crushing and processing of crushed concrete in order to become an alternative to natural gravel and rock aggregates; and educational and legislative where praxis in whole construction value chain needs a change.The goal of this project is the scale up concrete recycling process to produce climate-optimized carbonated aggregates of high quality by the transfer of knowledge and techniques from lab to industrial scale.

The concrete waste is made to partake in the reduction of CO2 emissions by a designed carbonation using flue gases from municipal waste incineration plants.

In a short-term this solution will help to reduce the landfilling and extraction of natural aggregates on a local level; and on a longer-term it will be a complementary technique for carbon capture and storage in building products.