Researchers at the largest geothermal facility in the world, The Hellisheidi power plant beat the time constraints predicted for carbon storage.
Storing carbon dioxide underground has been a problematic topic because of suspicions that the natural chemical reactions required would just take too much time.
It took less than two years for 95% of the injected carbon to solidify in the basalt below Hellisheidi. Exposing basalt to carbon dioxide and water causes several natural chemical reactions that allow carbon to change into a white mineral. The research shows there is no reason to fear any sort of explosions or emissions that could escape from underground.
Basalt, a type of sedimentary rock, is enriched with calcium, iron, and magnesium that can cause carbon to precipitate and form into a mineral. With the addition of substantial amounts of water, the carbon can be stored as a mineral instead of released into the atmosphere.
It’s important for the Hellishedi plant to store carbon dioxide. The plant produces energy for the capital Reykjavik in Iceland by using volcanically heated water for turbines that unfortunately has byproducts of carbon dioxide and hydrogen sulfide.
The research team pumped 250 tons of carbon dioxide, water, and hydrogen sulfide 400-800 meters into the ground. By monitoring a series of wells, results showed carbon isotopes in water samples that changed rapidly within months.
Past research has failed to turn up innovative ways to store carbon dioxide because experiments have pumped carbon dioxide into sandstone or salty aquifers. The pure carbon dioxide could in those cases escape through fractures or be released in the event of an earthquake or tremors.
The research has the potential to be applied to the other many power plants that have access to basalt. Fossil fuel facilities could take a lesson from the research prevented.