The Carbfix Project has captured carbon emissions from a power plant and turned them into storable stone, preventing the CO2 from entering the atmosphere.
Carbon dioxide is the largest contributor to climate change and remains in the atmosphere longer than any other heat-trapping gases. We have seen many attempts to reduce the production of CO2, such as producing carbon neutral or carbon negative building materials. In Iceland, engineers have found another potential solution. At Hellisheidi geothermal power plant, the Carbfix Project has captured carbon emissions and turned them into storable stone, so the CO2 does not enter the atmosphere.
The Carbfix Project is a collaboration between Reykjavik Energy and various universities. To begin the immobilization process, the scientists mixed the carbon dioxide and hydrogen sulfide released from the plant with water. Then, they injected the mixture into layers of basalt underground. The mixture then began to mineralize over the following months, creating a hard carbonate rock. The full transformation process takes around two years but is reliant on its proximity to underground volcanic basalt, so may not be able to be reproduced in less seismically active places. At the Hellisheidi plant, the process costs about USD 30 per ton of CO2, but this could also be significantly more expensive at coal-fired power plants.
Could the carbon stone be used in construction or other industries to make the process even more valuable?