Carbfix

Carbfix is a carbon capture and storage (CCS) method developed in Iceland. It accelerates the natural process of mineral carbonation, whereby carbon dioxide (CO2) reacts with basalt rock to form stable carbonate minerals, essentially turning the greenhouse gas into stone.

The Carbfix method involves dissolving CO2 in water and injecting the solution into subsurface basaltic formations. The slightly acidic water dissolves elements from the basalt rock, such as calcium, magnesium, and iron. These elements then react with the dissolved CO2 to form stable, environmentally benign carbonate minerals like calcite and magnesite.

Compared to traditional geological CO2 storage, which relies on trapping CO2 as a supercritical fluid in porous rock formations, Carbfix offers a potentially safer and more permanent storage solution. Mineral carbonation is thermodynamically stable, meaning the CO2 is permanently trapped in the rock and is highly unlikely to leak back into the atmosphere.

The Carbfix project has been implemented at the Hellisheiði geothermal power plant in Iceland, where CO2 captured from the plant's emissions is injected into the subsurface basalt. The results of the project have shown that a significant portion of the injected CO2 mineralizes within a relatively short timeframe, typically within months to a couple of years.

While Carbfix has shown promising results, it also has some limitations. It is only suitable for locations with abundant basalt rock formations. Furthermore, the process requires large volumes of water, which could be a concern in water-scarce regions. The cost of implementation can also be a factor, although ongoing research and development are aimed at reducing costs and improving efficiency. Despite these challenges, Carbfix represents a potentially valuable tool in the fight against climate change by offering a safe and permanent way to store CO2 emissions.