An international team of scientists have discovered a potentially viable way of removing anthropogenic (caused or influenced by humans) carbon dioxide (CO2) emissions from the atmosphere – by turning it into rock.
The study, published in Science, showed for the first time that the greenhouse gas can be quickly and permanently locked away by injecting it into volcanic bedrock.
Numerous measures to tackle increasing greenhouse gas emissions and resultant climate change have been explored. One such approach, Carbon Capture and Storage (CCS), involves CO2 being physically removed from the atmosphere and trapped underground, but this method is susceptible to leakage. Following the new investigation (part of the CarbFix project), attention has now turned to mineralisation of carbon as a means of permanently disposing of CO2.
Until now, it was thought that this process would take hundreds or even thousands of years to complete, but the current study – led by Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy, has demonstrated that it can take as little as two years.
Lead author Dr Juerg Matter, Associate Professor in Geoengineering at the University, said:
“Our results show that between 95 and 98 per cent of the injected CO2 was mineralised over the period of less than two years, which is amazingly fast.”
As a volcanic island, Iceland is made up of 90 per cent basalt, a rock rich in elements required for carbon mineralisation. CO2 dissolved in water was injected into a well at the study site in Iceland where, upon contact with the target rocks (400-800 metres under the ground), the solution reacted with the surrounding basalt to form carbonate minerals.
The study has appeared on BBC News online, The Guardian, The Economist and many other national and international media outlets.