Innovative CO2 Mineralization: A Game Changer for Climate Action
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Chapter 1: Transforming Carbon Emissions
The innovative approach of converting CO2 into solid minerals presents a promising solution for climate change. Iceland has pioneered a method that may represent a truly secure technique for capturing and storing carbon. Traditional carbon capture processes involve extracting CO2 from the atmosphere, compressing it, and then injecting it into underground formations. This method is often supported by the oil and gas sectors, which extract fossil fuels, inject CO2 back into the depleted reservoirs, and claim to be combating climate change. However, this approach is fraught with risks; CO2 can potentially escape back into the atmosphere, making it a temporary fix rather than a sustainable solution.
In contrast, the Icelandic method involves a chemical reaction between CO2 and mineral-rich rocks, resulting in a solid form of carbon. Under conventional carbon capture and storage techniques, this geological transformation could take over 100,000 years. Yet, researchers in Iceland have discovered a process that allows CO2 to be dissolved in water and injected into mineral-rich basalt rocks, converting it into solid calcite crystals in less than two years.
This process is not merely theoretical; it has been implemented industrially at CarbFix, which is part of the Hellisheidi geothermal power plant near Reykjavik, since 2014. CO2 is captured from the steam of the power plant, dissolved in large volumes of water, and then injected into the basalt at depths between 400 and 800 meters. The basalt, which contains significant amounts of calcium, magnesium, and iron, acts like a sponge, allowing the CO2 to settle and mineralize rapidly within a few hundred days.
Juerg Matter, an Associate Professor in Geoengineering at the University of Southampton and a key researcher in this project, notes that since 2016, CarbFix has scaled up its operations to inject approximately 10,200 tonnes of CO2 annually into basalt storage.
The carbon cycle informs us that all carbon—whether in the atmosphere, living organisms, or ourselves—originates from rocks and will ultimately return to that state. A 2014 study published in Science by the Institute of Earth Sciences at the University of Iceland highlights that human activities, particularly fossil fuel combustion, have hastened this cycle, leading to increased atmospheric CO2 levels, which drive global warming. Capturing and securely storing CO2 in geological formations is one method to mitigate this problem, helping to restore balance to the carbon cycle for extended periods.
Iceland is fortunate to have an abundance of basalt—over 90% of the island is comprised of this volcanic rock. However, basalt is not exclusive to Iceland; it constitutes around 10% of the Earth's surface and much of the ocean floor. As geologist Sandra Snaebjornsdottir from CarbFix explains, “This model can be applied wherever basalt and water are present. The potential storage capacity is immense, theoretically accommodating all CO2 emissions from fossil fuel combustion globally.”
So, why isn't this innovative method being adopted on a larger scale? Matter explains that the CarbFix approach is unique because it involves dissolving CO2 in water during the injection process, which isn't feasible everywhere due to water scarcity. However, preliminary findings from a pilot project in Washington State suggest that it might be possible to inject pure CO2 into deep basalt formations without the need for co-injection of water.
The dominance of conventional carbon storage methods can also be attributed to the oil and gas industry's control over the field, lacking experience with unconventional reservoirs like basalt. CarbFix, managed by Reykjavik Energy, emphasizes on its website that by capturing CO2 from various sources and injecting it into appropriate geological formations, carbon can be returned to its original state, contributing to climate change mitigation. This approach significantly reduces the risk of leakage and avoids passing the burden to future generations.
While it is crucial to prioritize the reduction of carbon emissions, establishing a reliable method of carbon capture adds a valuable tool to our efforts against global warming.
The first video, "Can Turning CO2 to Stone Help Save the Planet?" explores the transformative potential of this innovative technology in addressing climate challenges.
The second video, "The Climate Tech that turns CO2 into rock," delves into how this approach can reshape our understanding of carbon capture and climate action.