Carbon dioxide can be captured in rock without using external water

A new paper published yesterday in the science journal Nature marks an important development of carbon capture and storage and shows clearly how fundamental research can evolve into solutions that have a significant impact on business, the environment and society.

Among the authors of the article in Nature are Eric Oelkers, the lead author who has served for years as a Guest Professor at the Institute of Earth Sciences at the University of Iceland, and Sigurður Reynir Gíslason, Professor at the Institute of Earth Sciences. Both have been at the forefront of research on water rock interactions and storing carbon dioxide as minerals in reactive rocks.

The article, entitled “CO₂ subsurface mineral storage by its co-injection with recirculating water” establishes that carbon dioxide can be permanently stored in the Earth’s subsurface without using external water in addition to that which is found in the injection area’s subsurface.

This project is based on the Carbfix method which was developed in Iceland. Carbon dioxide gas is dissolved in water and transformed into stable carbonate minerals. This method has already gained international attention for its speed and safety, where carbon dioxide becomes a solid part of the rock.

Another Icelander, Grímur Björnsson, geophysicist and geothermal reservoir engineer, is also part of the research group. He was one of the innovators behind the Carbfix project in its early days. Several authors are from two research groups from Saudi Arabia, where the new injection project took place. One is from King Abdullah University of Science and Technology (KAUST), and the other is from the company ARAMCO.

Water that was Previously Lacking is Now Part of the Solution

”In this new field experiment in Western Saudi Arabia, we’re addressing one of the biggest challenges in carbon capture and mineral storage — high demand for water. Instead of relying on external water, we’re using water that’s already there in the subsurface,” Sigurður Reynir Gíslason, Professor at UI says.

‘It’s pumped from one well and then reinjected into another well with the carbon dioxide gas, where the gas dissolves in the water and acidifies it. When acidic water encounters the rock, it releases elements like carbon dioxide that can combine with the dissolved carbon to form carbonate  minerals such as calcite. Thereby turning gas into stone. As a result, the gas concentration in the water decreases. This water flows to the source well and is then reinjected with more carbon dioxide gas into the injection well and reused in a closed circular system between the wells.”

According to Sigurður, this approach provides new opportunities. ‘Water has, until now, been a limiting factor in arid regions. Now we have the possibility of using carbon capture and mineral storage in conditions that were previously thought to be unrealistic.’

Sigurður also states that the results demonstrate that the process is both fast and efficient: a large part of the carbon dioxide is stored in the subsurface within a year, thereby permanently removing it from the global carbon cycle. There’s no need to elaborate on how important this is for the environment and the climate.

Icelandic Research Lay the Foundation for a New Climate Solution in Saudi-Arabia

The field injection experiment published yesterday in Nature, was conducted in western Saudi Arabia where basaltic rocks are abundant, and carbon emissions from industry are high. Despite the conditions being different from those in Iceland, the connection is clear. The project is based on new scientific findings and the Carbfix method developed in Iceland by the Carbfix project between 2006 and 2020, and after that by the Carbfix company. This is one of the most well-known examples of how fundamental research in Iceland has resulted in innovation and industrial activity with international impact.

From University to Industry: Knowledge in Practice

The contributions of Sigurður Reynir Gíslason and the team he has led have been a crucial factor in the progress made so far. Research on the interaction between water, carbon dioxide, and basaltic rocks, which for a long time was primarily fundamental geochemical research, has gradually evolved into an important technological solution for climate mitigation. This development shows clearly that investment in fundamental research is not only done on knowledge-based purposes but can lead to effective solutions for communities worldwide.

In this context, the new article in Nature is not only an important scientific finding but also a reminder of the societal role of universities and research. It demonstrates how knowledge generated in an academic environment can evolve into practical solutions that support sustainable development, reduce greenhouse gas emissions, and create new opportunities in industry.

The University of Iceland has played a major role in this development, for example through the many doctoral students involved in the Carbfix project. ‘With continued collaboration between scientists, industry, and society, it is clear that the Carbfix method will continue to evolve and be applied in more and more locations around the world,’ Sigurður Reynir says.

Carbfix – From Research to a Company with International Impact

Carbfix is an Icelandic company, partly owned by the University of Iceland, that has developed a method, as mentioned earlier, to permanently store carbon dioxide in rock by dissolving it in water and converting it into stable minerals in basalt.

The technology is based on decades of fundamental research, including work at the University of Iceland, on the interaction between water, carbon dioxide, and reactive rocks. With this approach, carbon becomes part of the rock itself, and the risk of leakage is negligible. Carbfix has already been implemented in Iceland, for example at the Hellisheiði Power Plant, and has attracted international attention. The project is one of the clearest examples of how fundamental research in universities can evolve into real-world applications with highly positive impacts on both climate and society.

Other authors of the Nature article, in addition to Eric, Sigurður, and Grímur, are: Serguey Arkadakskiy, Zeyad Ahmed, Noushad Kunnummal, Jakub Fedorik, Massimo Marchesi, Mouadh Addassi, Abdirizak Omar, Niccolo Menegoni, Davide Berno, Thomas Finkbeiner, Abdulkader Afifi, and Hussein Hoteit.