Carbon stored in basalt formation
CO2 mineralization, where carbon dioxide reacts with minerals to create rock formations, makes permanent storage on a virtually unlimited scale possible. It is one of the most promising climate mitigation options. Basaltic rocks, which primarily consist of magnesium and calcium silicate minerals, provide alkaline earth metals necessary to form solid carbonates. Once the carbon dioxide has reacted with minerals, it becomes part of a solid material and cannot be re-released into the atmosphere. In-situ mineralization occurs when carbon dioxide is injected directly into geologic formations of these absorptive minerals. Ex-situ mineralization occurs in a laboratory, using chemicals to accelerate reaction times .
The CO2 at Hellisheidi Iceland will be stored as solid calcium carbonate mineral in basaltic rock.
The CarbFix pilot program, a combined industrial-academic program was developed in order to assess the feasibility of in situ CO2 mineral sequestration in basaltic rocks. Started in 2010, this program involves the CNRS, the University of Iceland, Reykjavik Energy, and Columbia University in N.Y. Unique to CarbFix is its connection to the Hellisheidi geothermal power plant, allowing for capture of otherwise emitted CO2 in addition to CO2 transport and mineral sequestration .