Turn carbon dioxide into stone for permanent storage

Under the pressure of reducing greenhouse gas emissions, energy companies have high expectations for carbon capture and storage technologies. Storage sites are often located in abandoned oil and gas fields, or even deep seabeds. However, there are also concerns about the risk of leakage of sequestered carbon dioxide. A research team in Iceland said that their storage methods will reduce or even eliminate carbon dioxide leakage concerns, which is a permanent storage method.

The plan named CarbFix was launched in Iceland in 2007. Iceland is rich in geothermal resources, geothermal power accounts for 30% of the country's electricity consumption, but the hot gas emitted by geothermal power stations contains carbon dioxide. The treatment of these carbon dioxide first needs to be separated and transported to the storage area of ​​the basalt structure. Iceland has a large amount of basalt, which injects carbon dioxide into basalt. Carbon dioxide reacts with calcium and magnesium, which are abundant in basalt, and becomes permanently buried underground in limestone.

However, the progress of the project is not always smooth. In the gas separation section, team members encountered unexpected troubles. The gas mixture contains *H2O, which is highly corrosive and the separation equipment is often corroded. In addition, equipment needs to be developed to detect the situation after CO2 is injected into the ground. The research team also needed a system to transport carbon dioxide from the place of production to the storage site. Moreover, the entire process from the separation to the storage of carbon dioxide is also a process of energy consumption intensive and requires a lot of electricity and water. Adatan, the project manager of CarFix, said that the cost of the trial is high and it has not entered the commercialization stage.

Iceland is an ideal carbon storage site because 90% underground in the country is basalt. Most of the world's land is located on basalt, which means that this technology can be widely used to deal with climate change.

CargFix Project Manager Jorge? Matt is still full of confidence in this project. He said: "The potential of this technology has been further manifested. After the first storage, the possibility of CO2 leakage is very small and the storage is permanent. Second, with the advancement of technology, the cost is also high. It will continue to decrease and it will be an effective way to control greenhouse gas emissions."

Matt said: "My vision for carbon capture and storage is sea bottom storage. The bottom of the entire ocean is basalt, which is located below the sediment."