Carbon sink lightweight concrete

Important results from the project

The aim of the project was to contribute to improving the climate impact of the concrete industry by incorporating biochar into construction products to create a carbon sink. The project also aimed to strengthen the Swedish bio-industry through the upgrading of bio-based residual materials. The project carried out several product development steps and identified residual streams for the application. Created carbon sink and climate benefits have been calculated and tracking systems have been determined. However, the specified needed biochar production needs to be developed.

Expected long term effects

The project has addressed the entire value chain from the use of bio-industrial and bio-energy residues to biochar production, biochar preparation (grinding) and concrete recipe development. The project has resulted in a couple of products with the desired function and strength. An aim of the project was to exemplify how a circular carbon economy can work. The project has generated international interest and collaborations. The value chain with the end-products in the project indicate that the solution has substantial potential to impact carbon sink creation in the building sector.

Approach and implementation

The methodology to test the project hypothesis was to go through all stages of the value chain; from pyrolysis to building product manufacturing. The availability of suitable biochar according to the identified project requirements was limited and work hade to be devoted to find a solution for the project´s concrete trials. Different biochar was tested in different construction products. Both soft and hard values were parameters in assessing the possible biochar quantity in the applications. The actual trial casting and trial production of biochar went more smoothly than expected.