Volcanic Basalt Rock for Permanent CO₂ Mineralization: Advances in Carbon Sequestration

Volcanic Basalt Rock for Permanent CO₂ Mineralization: Advances in Carbon Sequestration

The urgent need to mitigate climate change has propelled research into effective carbon sequestration methods capable of securely storing CO₂ emissions over geological timescales. Among these, mineral carbonation within basalt rocks offers a promising solution by converting injected CO₂ into stable carbonate minerals. Projects such as Iceland’s CarbFix and Norway’s Northern Lights and PERBAS initiatives are pioneering this approach, leveraging the unique properties of basalt and related rock formations to enhance carbon capture and storage.

Mechanisms and Benefits of Rapid Mineral Carbonation in Basalt Rocks

Basaltic rocks, particularly young formations rich in reactive minerals like calcium, magnesium, and iron, facilitate rapid mineral carbonation through chemical reactions that convert CO₂ into solid carbonate minerals such as calcium carbonate (limestone), magnesium carbonate (magnesite), and dolomite. This process immobilizes CO₂ permanently, reducing risks of leakage common in traditional geological carbon storage methods.

One of the significant advantages of basalt is the accelerated rate of carbonation compared to sedimentary formations. Field evidence from the CarbFix project demonstrates that over 90% of injected CO₂ mineralizes within two years, a rapid transformation enhanced by dissolving CO₂ in water before injection. This approach reduces CO₂ buoyancy, promotes subsurface stability, and ensures more effective carbon binding within the rock matrix.

Basalt’s global abundance, particularly in volcanic and mid-ocean ridge regions, provides substantial opportunities for industrial-scale CO₂ mineralization. These rocks’ mineral composition inherently supports effective geological storage by forming carbonate minerals that are stable over millions of years.

Technical and Environmental Risks of Subsea CO₂ Injection and Mineralization

Subsea basalt storage expands carbon sequestration potential but introduces complex technical and environmental challenges. Injecting CO₂ beneath the seabed entails risks such as:

• Potential leakage if mineralization is incomplete or containment fails.
• Variability in rock permeability and heterogeneity affecting CO₂ injection efficiency.
• Induced seismicity caused by pressure changes in tectonically active zones.
• Possible impacts on marine ecosystems requiring comprehensive environmental impact assessment and ongoing monitoring.

Moreover, legal frameworks regulating subsea carbon storage are still evolving, encompassing issues related to transboundary resource management and public acceptance. Transparent risk assessments and stakeholder engagement remain critical for advancing subsea projects.

Case Studies: CarbFix in Iceland and Northern Lights and PERBAS Projects in Norway

CarbFix Project, Iceland: The CarbFix initiative illustrates successful industrial-scale CO₂ mineralization by injecting CO₂ dissolved in water into basalt formations near the Hellisheiði geothermal power plant. This method has achieved over 90% conversion of CO₂ into carbonate minerals within two years, highlighting the feasibility and permanence of mineral carbonation in volcanic basalt.

Northern Lights Project, Norway: This collaboration between Equinor, Shell, and TotalEnergies focuses on capturing CO₂ from European industrial sources, transporting it to offshore sandstone reservoirs, and developing subsea injection infrastructure in the North Sea. While targeting sedimentary reservoirs, the project supports broader carbon sequestration infrastructure in the region.

PERBAS Project, Norway: Complementing basalt efforts, PERBAS investigates CO₂ mineralization potential in peridotite rock, an ultramafic formation rich in magnesium and calcium. This research aims to diversify geological carbon storage options by exploring mineral carbonation beyond basalt.

Advantages of Basalt’s Mineral Composition for Carbon Mineralization

Basalt’s reactive mineral content—including calcium, magnesium, and iron—enables efficient chemical binding of CO₂ through mineral carbonation. This results in the formation of various stable carbonate minerals, providing a secure and durable carbon sink. Additionally, the rock’s porosity and permeability support CO₂ injection and fluid flow, which are essential for successful geochemical reactions.

Geological and Regulatory Challenges in Seabed CO₂ Storage

Storing CO₂ beneath the seabed involves addressing geological uncertainties, including reservoir heterogeneity and the kinetics of mineral formation. Regulatory considerations center on the long-term liability, monitoring requirements, and adherence to international maritime and environmental laws. Establishing clear guidelines and obtaining social license to operate remain pivotal for the deployment of subsea carbon storage solutions.

Role of Mid-Ocean Ridge and Volcanic Regions in Carbon Capture

Volcanic regions and mid-ocean ridges are naturally endowed with extensive basalt formations suitable for CO₂ mineralization. These geological settings provide widespread opportunities for carbon capture and permanent storage, leveraging the intrinsic geochemical properties of basalts to convert CO₂ rapidly and stably. Efforts to harness these regions through projects like CarbFix signify critical advances toward scalable carbon capture technologies.

Conclusion

Basalt-hosted CO₂ mineralization stands out as a secure, efficient, and permanent method for geological carbon storage. Demonstrated success from projects in Iceland and Norway highlights the potential of converting CO₂ into carbonate minerals within reactive volcanic rock formations. While subsea CO₂ injection expands storage capacity, it also introduces technical, environmental, and regulatory complexities that must be managed carefully. Continued innovation and comprehensive assessment in these areas are essential to harness basalt’s full potential in global climate mitigation strategies.

Frequently Asked Questions

Q: How does CO2 mineral storage work

A: CO2 mineral storage involves capturing carbon dioxide and reacting it with certain types of rock, like basalt or serpentine, to form stable minerals such as carbonates. This process mimics natural weathering but occurs much faster in controlled conditions. The CO2 is either injected underground where it reacts with minerals or processed in reactors to accelerate mineral formation, trapping the carbon permanently and preventing its release back into the atmosphere.

Q: Can volcanic basalt store carbon dioxide permanently

A: Yes, volcanic basalt can store carbon dioxide permanently through a process called mineral carbonation. When CO2 is injected into porous basalt rock formations, it reacts with the minerals to form stable carbonate minerals, effectively locking away the carbon for thousands to millions of years. This method is considered a promising approach to long-term carbon capture and storage because basalt is abundant, reactive, and widely distributed around the world.

Q: Carbfix CO2 storage technology Iceland

A: Carbfix is an innovative CO2 storage technology developed in Iceland that captures carbon dioxide and rapidly converts it into stable minerals underground. The process involves dissolving CO2 in water and injecting the solution into basaltic rock formations, where it chemically reacts to form solid carbonate minerals within months. This method offers a safe, permanent, and scalable way to reduce atmospheric CO2, leveraging Iceland's abundant volcanic geology to store carbon effectively.

Q: Risks of CO2 leakage in seabed storage

A: CO2 leakage in seabed storage poses several risks, including the potential release of stored carbon dioxide into the ocean and atmosphere, which could undermine climate mitigation efforts. Leakage may also acidify surrounding seawater, harming marine ecosystems and biodiversity. Additionally, sudden releases could cause pressure changes that might damage geological formations or infrastructure, leading to environmental and safety concerns. Monitoring and robust site selection are essential to minimize these risks.

Q: Carbon capture projects in Norway and Iceland

A: Norway and Iceland are leaders in carbon capture and storage (CCS) technologies, focusing on reducing industrial CO2 emissions. Norway's notable project is the Northern Lights initiative, part of the broader Longship CCS project, which captures CO2 from industrial sources and stores it under the seabed in the North Sea. Iceland hosts the CarbFix project, which innovatively captures CO2 and injects it into volcanic basalt formations, where the carbon mineralizes into stable rock rapidly. Both countries leverage their geological settings to advance carbon capture, helping mitigate climate change.

Key Entities

Carbfix: Carbfix is an Icelandic project focused on carbon capture and storage by injecting CO2 into basaltic rock formations where it mineralizes rapidly. The project aims to offer a scalable solution to mitigate climate change by permanently storing carbon underground.

University of Bergen: The University of Bergen is a Norwegian public university known for its marine research and climate studies. It plays a key role in studies related to oceanography, geosciences, and environmental sciences.

Northern Lights project: The Northern Lights project is a pioneering joint venture in carbon capture and storage in Norway, aiming to transport and permanently store CO2 under the North Sea seabed. It is part of Norway's broader efforts to develop large-scale CCS infrastructure.

Institute for Energy Technology (IFE): The Institute for Energy Technology (IFE) is a Norwegian research organization specializing in nuclear technology, renewable energy, and carbon capture technologies. IFE contributes to development of innovative solutions to support carbon emission reduction.

GEOMAR: GEOMAR Helmholtz Centre for Ocean Research Kiel is a leading German marine science institute conducting research on ocean dynamics and climate impacts. Its work includes studying the effects and feasibility of carbon storage in marine environments.

External articles

• Basalts Turn Carbon into Stone for Permanent Storage - Eos.org
• CO2 Geological Sequestration in Basalt Formations
• Carbon dioxide sequestration in deep-sea basalt - PMC

YouTube Video

Title: Pioneering cross-border Carbon Capture and Storage (CCS) with liquefied CO2 shipping
Channel: Shell
URL: https://www.youtube.com/watch?v=o2R-r4-lTMc
Published: 6 months ago