Icelanders turn carbon dioxide (CO2) emissions into stone

One of the CarbFix installations

The Icelandic CarbFix project has confirmed the effectiveness of greenhouse carbon dioxide utilization by pumping into volcanic rocks for mineralization. An international group of experts published the results of experiments in the journal Science .

The CarbFix project was launched in 2012. The pilot facility for the utilization of carbon dioxide emitted by the nearby Hedlisheidi geothermal power plant is located about 25 kilometers from Reykjavik. Gas dissolved in water was pumped into the well of a two-kilometer depth, another eight less deep wells served for monitoring. The layers of basalt and hyaloclastites absorbing carbon dioxide are located at a depth of 400 to 800 meters and are covered with a layer of low-permeable hyaloclastites.


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In the first phase of the experiment, from January to March 2012 , 175 tons of carbon dioxide dissolved in water were pumped into the well, the second from June to August of the same year, 73 tons of a mixture of carbon dioxide and hydrogen sulfide, which is also released by the power plant. For convenience of monitoring, carbon dioxide containing radioactive carbon-14 and radioactively labeled volatile hexafluoride and sulfur trifluoromethylpentafluoride were added to the solutions.

Observations showed that within two years more than 95% of carbon dioxide reacted with the surrounding rock and was mineralized to form carbonate rocks (mainly calcite), which eliminates the risk of its leakage to the atmosphere. According to project manager Edda Aradóttir (Edda Aradóttir), such utilization rates surprised the designers themselves.



The cost per ton is $ 30, which is cheaper than traditional methods that require from $ 65 to $ 100 per ton.
According to Aradottir, high water consumption - 25 tons per ton of carbon dioxide - is not a problem, because saline ocean water is suitable for these purposes. She added that basalt lavas covered about 10 percent of the land and almost the entire ocean floor, so the technology of carbon dioxide mineralization has great prospects for use.

Global carbon emissions

The fault of man - 9.795 Gt (gigaton) of carbon (or 35.9 Gt of carbon dioxide CO ₂ ) per year (2014)
Natural cycle - 119 Gt of carbon ^wiki (or 439 Gt of carbon dioxide CO ₂ ) // (decomposition of organic matter, volcanic activity, forest fires, etc.)

Regarding the natural cycle of C and CO ₂ , people do not make a significant contribution, but the problem is that the natural cycle balances itself within safe limits (oceans, dissolving CO ₂ , transform it into H ₂ CO ₃ , plants use CO ₂ for photosynthesis, etc. ). And, as a result of human activity, additional CO ₂ does not disappear without a trace (60% -70% CO2 is there, in the atmosphere and remains, which contributes to the heating of the planet, and the remaining 30% -40% are absorbed by the oceans and seas, which leads them to a general decrease in pH)

Efficiency of CarbFix

Currently, the project mineralizes 5,000 tons of carbon dioxide annually.
In the summer of 2016, it is planned to install new equipment, which will double this amount (after which, to reduce CO ₂ emissions caused by human activity, to zero, CarbFix would need 970,000 of these complexes, if CarbFix was the only project that reduces CO emissions ₂ on the planet, but unfortunately, there are several other sane companies, like Tesla, and governments that promote the development of renewable energy sources).