Carbfix is an Icelandic company founded in 2007. It has developed an approach to permanently store CO2 by dissolving it in water and injecting it into basaltic rocks. Once in the subsurface, the injected CO2 reacts with the host rock forming stable carbonate minerals, thus providing permanent storage of the injected CO2[1]

Carbfix
IndustryCarbon sequestration
Founded2007
FoundersReykjavík Energy, the University of Iceland, CNRS, and the Earth Institute at Columbia University
Headquarters,
Websitehttps://www.carbfix.com/

Approximately 200 tons of CO2 were injected into subsurface basalts in a first-of-a-kind pilot injection in SW-Iceland in 2012. Research results published in 2016 showed that 95% of the injected CO2 was solidified into calcite within 2 years, using 25 tons of water per ton of CO2.[2][3][4] Since 2014, this technology has been applied to the emissions of the Hellisheiði Geothermal Power Plant. H2S and CO2 are co-captured from the emission stream of the power station and permanently and safely stored via in-situ carbon mineralization at the Húsmúli reinjection site.[5] The process captures approximately one-third of the CO2 emissions (12,000 tCO2/y) and 60% of the H2S emissions (6,000 tH2S/y) from the power plant. The Silverstone project aims to deploy full-scale CO2 capture, injection, and mineral storage at the Hellisheiði Geothermal Power Plant from 2025 onwards.[6]

Carbfix is currently operating four injection sites in Iceland in relation to the Hellisheiði Geothermal Power Plant: the Nesjavellir Geothermal Power Plant, The Orca direct air capture plant near Hellisheiði and within the CO2 Seastone project in Helguvík (see chapter “Current status”).

Background

edit

Carbfix was founded by the then Icelandic President, Dr Ólafur Ragnar Grímsson, Einar Gunnlaugsson at Reykjavík Energy, Wallace S. Broecker at Columbia University, Eric H. Oelkers at CNRS Toulouse (France), and Sigurður Reynir Gíslason at the University of Iceland to limit the Greenhouse gas emissions in Iceland.[7] Reykjavik Energy supplied the initial funding for Carbfix. Further funding has been supplied by The European Commission and the Department of Energy of the United States. In addition to finding a new method for permanent carbon dioxide storage, another objective of the project was to train scientists.[8]

Method

edit
 
Image of calcite formed in basalt due to CO2-charged water-rock interaction at the Carbfix site

Captured CO2 is dissolved in water, either prior to or during injection into mafic or ultramafic formations, such as basalts. The dissolution of CO2 in water can be expressed as:

CO2 (g) H2O(l) ⇌ H2CO3 (aq)

↔ H (aq) HCO3- (aq)

↔ 2H (aq) CO32-(aq)

By dissolving the CO2 in water instant solubility trapping is achieved, which is the second most secure trapping mechanism of CO2 storage:[9] No CO2 bubbles are present in the CO2-charged water, which is furthermore denser than the water that is present in the formation, so that the CO2-charged water has rather the tendency to sink than to migrate upwards towards the surface.[10]

The CO2-charged water is acidic, typically having a pH of 3-5 depending on the partial pressure of CO2, water composition, and the temperature of the system. The CO2-charged water reacts with the subsurface rocks and dissolves cations such as Calcium, Magnesium, and Iron.[11] The dissolution of cation-bearing silicate minerals; for example, the dissolution of pyroxene, a common mineral in basalt and peridotite, can be expressed as:

2H H2O (Ca,Mg,Fe)SiO3 = Ca2 , Mg2 , Fe2 H4SiO4

The cations can react with the dissolved CO2 to form stable carbonate minerals, such as Calcite (CaCO3), Magnesite (MgCO3), and Siderite (FeCO3), a reaction that can be expressed as:  

Ca2 ,Mg2 ,Fe2 (aq) CO32-(aq) → CaCO3 (s), MgCO3 (s), FeCO3 (s)

Ultramafic and mafic rock formations are most efficient due to their high reactivity and their abundance in divalent metal cations. The degree to which the released cations form minerals depends on the element, the pH and the temperature.[1]

Practicalities

edit

Drilling and injecting carbonated water at high pressure into basaltic rocks at Hellisheiði has been estimated to cost less than $25 a ton.[12]

This project commenced carbon injection in 2012.[13][14][15][16] The funding was supplied by the University of Iceland, Columbia University, France's National Centre of Scientific Research, the United States Department of Energy, the EU, Nordic funds and Reykjavik Energy.[14]

These funding sources include the European Union's Horizon 2020 research and innovation programme under grant agreements No. 764760 and 764810. The European Commission through the projects CarbFix (EC coordinated action 283148), Min-GRO (MC-RTN-35488), Delta-Min (PITN-GA-2008-215360), and CO2-REACT (EC Project 317235). Nordic fund 11029-NORDICCS; the Icelandic GEORG Geothermal Research fund (09-02-001) to S.R.G. and Reykjavik Energy; and the U.S. Department of Energy under award number DE-FE0004847.

Cost is around US$25 per tonne of CO2.[17]

Challenges

edit

Reinjection of geothermal fluid from the Hellisheiði Geothermal Power Plant started in Húsmúli reinjection field, in September 2011. Commissioning of the reinjection site caused significant induced seismicity that was felt in nearby communities.[18][19] This problem was addressed by introducing a new workflow where preventive steps are taken to minimize this risk, including the adjustment of the injection rates.[20] The implementation of the workflow resulted in the decrease of the annual number of seismic events greater than magnitude 2 in the area from 96 in 2011 to one in 2018,[21] which is considered satisfactory and demonstrates that current operations are within regulatory boundaries.

Carbfix started injection of CO2 captured from the Hellisheiði Geothermal Power Plant and dissolved in condensate from the plant’s turbines into one of the existing reinjection wells in the Húsmúli reinjection field in April 2014.[22] No increased seismicity was noted after the injection of CO2 started implying that seismicity is not induced by the injection of the condensate-dissolved CO2.[23]

Current status

edit
 
The Hellisheiði Geothermal Power Plant is the site of the original Carbfix project, which injected approximately 200 tons of CO2 into the subsurface and fixed it as stable carbonate minerals.

Carbfix is currently operating four injection sites in Iceland with emphasis on injection of CO2 captured from point-sources of CO2, CO2 that is captured and transported to an injection site, and CO2 that is captured directly from the atmosphere using direct air capture (DAC) technology.[24]

Point source capture and mineral storage of CO2

Carbfix has since June 2014 captured and injected CO2 and hydrogen sulfide (H2S) from Hellisheiði Geothermal Power Plant. The geothermal gases are dissolved in condensate from the power plant’s turbines in a specially designed scrubbing tower and injected to a depth of 750 m underground into basaltic rocks.[5][25] Currently about 68% of the H2S and 34% of the CO2 from the plant’s emissions are captured and injected, which amounts to about 12,000 tons of CO2 per year, and about 5,000 tons of H2S per year.[5] Results show that over 60% of the injected CO2 was mineralized within 4 months of injection, and over 85% of the injected H2S within 4 months of injection.[26]

Carbfix is currently working on scaling up the operations at the Hellisheiði Geothermal Power Plant through the EU Innovation Fund project Silverstone, aiming for near-zero geothermal power production from 2025 by capturing over 95% of CO2 and 99% of H2S from the plant’s emissions. This accounts for up to 40,000 tons of CO2 and up to 12,000 tons of H2S per year.[27]

Carbfix has since early 2023 started the capture and injection of CO2 and H2S from the Nesjavellir Geothermal Power Plant in SW-Iceland as a part of the Europe Horizon 2020 funded GECO project.[28] The same approach is used as at the Hellisheiði Geothermal Power Plant, but with optimized capturing efficiency of the scrubbing tower. The gases are dissolved in condensate from the plant‘s turbines and injected into the basaltic subsurface below 900 m.[29]

Injection and mineral storage of CO2 captured from the atmosphere using direct air capture technologies

The world’s first injection of CO2 captured from the atmosphere was carried out in Hellisheiði in SW-Iceland in 2017, as part of the Europe H2020 funded project CarbFix2. The CO2 was captured using a Direct Air Capture (DAC) unit developed by the Swiss green-tech company Climeworks. The CO2 was then dissolved in water and injected into the basaltic subsurface.[30][31]

In 2021, the world’s first commercial DAC combined with storage plant, Orca, was commissioned in Hellisheiði in collaboration between Climeworks and Carbfix. The plant has the capacity to capture up to 3,600 tons of CO2 directly from the atmosphere that are injected into basalts for permanent mineral storage.[32]

In 2024 Climeworks and Carbfix are commissioning the Mammoth DAC plant, with the capacity to capture up to 36,000 tons per year which will be injected into the basalt for permanent mineral storage at the Geothermal Park in Hellisheiði.[33][34]

CO2 capture, transport and storage

Cross-border transport of CO2 was first demonstrated as part of the DemoUpCarma project in August 2022.[35] The project was funded by the Swiss Federal Offices and led by ETH.[36][37] The CO2 was captured from a biogas upgrading plant in Bern, Switzerland, and transported to Iceland where it was first injected at the Hellisheiði site. The current injection site of DemoUpCarma project is in Helguvík, Iceland, where the CO2 is co-injected with seawater as part of the R&D project CO2Seastone.[38]

In July 2021, Carbfix was awarded the largest research grant ever granted to an Icelandic company, when it was nominated for the EU Innovation Fund grant of 15 million EU for the Coda Terminal project.[39][40]

The Coda Terminal will be developed in Straumsvík, SW-Iceland as the first cross-border carbon transport and storage hub in Iceland. CO₂ will be captured at industrial sites in N-Europe, focusing on the hard-to-abate sector, and shipped to the Terminal where it will be unloaded into onshore tanks for temporary storage. The CO₂ will then be pumped into a network of nearby injection wells where it will be dissolved in water during injection into the basaltic bedrock. The operations will be scaled up in steps reaching up to 3 million tons of CO₂ per year from 2031.[41]

References

edit
  1. ^ a b Snæbjörnsdóttir, Sandra Ó.; Sigfússon, Bergur; Marieni, Chiara; Goldberg, David; Gislason, Sigurður R.; Oelkers, Eric H. (2020-01-20). "Carbon dioxide storage through mineral carbonation". Nature Reviews Earth & Environment. 1 (2): 90–102. Bibcode:2020NRvEE...1...90S. doi:10.1038/s43017-019-0011-8. ISSN 2662-138X.
  2. ^ Matter, Juerg M.; Stute, Martin; Snæbjörnsdottir, Sandra Ó.; Oelkers, Eric H.; Gislason, Sigurdur R.; Aradottir, Edda S.; Sigfusson, Bergur; Gunnarsson, Ingvi; Sigurdardottir, Holmfridur; Gunnlaugsson, Einar; Axelsson, Gudni; Alfredsson, Helgi A.; Wolff-Boenisch, Domenik; Mesfin, Kiflom; Taya, Diana Fernandez de la Reguera (2016-06-10). "Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions". Science. 352 (6291): 1312–1314. Bibcode:2016Sci...352.1312M. doi:10.1126/science.aad8132. ISSN 0036-8075. PMID 27284192.
  3. ^ Toor, Amar (2016-06-10). "Scientists turn carbon dioxide into stone to combat global warming". The Verge. Retrieved 2024-05-23.
  4. ^ Le Page, Michael (2016-06-09). "CO2 injected deep underground turns to rock – and stays there". New Scientist. Retrieved 2024-05-23.
  5. ^ a b c Sigfússon, Bergur; Arnarson, Magnús Þór; Snæbjörnsdóttir, Sandra Ósk; Karlsdóttir, Marta Rós; Aradóttir, Edda Sif; Gunnarsson, Ingvi (July 2018). "Reducing emissions of carbon dioxide and hydrogen sulphide at Hellisheidi power plant in 2014-2017 and the role of CarbFix in achieving the 2040 Iceland climate goals". Energy Procedia. 146: 135–145. Bibcode:2018EnPro.146..135S. doi:10.1016/j.egypro.2018.07.018.
  6. ^ "Project Silverstone". www.carbfix.com. Retrieved 2024-05-23.
  7. ^ Gíslason, Sigurður R.; Sigurðardóttir, Holmfriður; Aradóttir, Edda Sif; Oelkers, Eric H. (July 2018). "A brief history of CarbFix: Challenges and victories of the project's pilot phase". Energy Procedia. 146: 103–114. Bibcode:2018EnPro.146..103G. doi:10.1016/j.egypro.2018.07.014.
  8. ^ "That CO2 warming the world: Lock it in a rock". Retrieved 11 October 2011.2 warming the world: Lock it in a rock&rft_id=http://www.mercurynews.com/science-headlines/ci_18773956&rfr_id=info:sid/en.wikipedia.org:Carbfix" class="Z3988">
  9. ^ Benson, S.M.; Cook, P.; Anderson, J.; Bachu, S.; Nimir, H.B.; Basu, B.; Bradshaw, J.; Deguchi, G.; Gale, J. (January 2005). "Underground Geological Storage, IPCC Special Report on Carbon Dioxide Capture and Storage, Chapter 5". Intergovernmental Panel on Climate Change, Cambridge University Press Cambridge, U.K.
  10. ^ Sigfusson, Bergur; Gislason, Sigurdur R.; Matter, Juerg M.; Stute, Martin; Gunnlaugsson, Einar; Gunnarsson, Ingvi; Aradottir, Edda S.; Sigurdardottir, Holmfridur; Mesfin, Kiflom; Alfredsson, Helgi A.; Wolff-Boenisch, Domenik; Arnarsson, Magnus T.; Oelkers, Eric H. (June 2015). "Solving the carbon-dioxide buoyancy challenge: The design and field testing of a dissolved CO2 injection system". International Journal of Greenhouse Gas Control. 37: 213–219. doi:10.1016/j.ijggc.2015.02.022. ISSN 1750-5836.
  11. ^ Gislason, Sigurdur R.; Oelkers, Eric H. (2014-04-25). "Carbon Storage in Basalt". Science. 344 (6182): 373–374. Bibcode:2014Sci...344..373G. doi:10.1126/science.1250828. ISSN 0036-8075. PMID 24763582.
  12. ^ Gunnarsson, Ingvi; Aradóttir, Edda S.; Oelkers, Eric H.; Clark, Deirdre E.; Arnarson, Magnús Þór; Sigfússon, Bergur; Snæbjörnsdóttir, Sandra Ó.; Matter, Juerg M.; Stute, Martin; Júliusson, Bjarni M.; Gíslason, Sigurður R. (December 2018). "The rapid and cost-effective capture and subsurface mineral storage of carbon and sulfur at the CarbFix2 site" (PDF). International Journal of Greenhouse Gas Control. 79: 117–126. Bibcode:2018IJGGC..79..117G. doi:10.1016/j.ijggc.2018.08.014.
  13. ^ Matter, Juerg M.; Stute, Martin; Snæbjörnsdottir, Sandra O.; Oelkers, Eric H.; Gislason, Sigurdur R.; Aradottir, Edda S.; Sigfusson, Bergur; Gunnarsson, Ingvi; Sigurdardottir, Holmfridur; Gunlaugsson, Einar; Axelsson, Gudni; Alfredsson, Helgi A.; Wolff-Boenisch, Domenik; Mesfin, Kiflom; Fernandez de la Reguera Taya, Diana; Hall, Jennifer; Dideriksen, Knud; Broecker, Wallace S. (June 10, 2016). "Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions". Science. 352 (6291): 1312–1314. Bibcode:2016Sci...352.1312M. doi:10.1126/science.aad8132. PMID 27284192.
  14. ^ a b "Iceland's Hellisheidi prepares to start injection at carbon storage project". 9 September 2011. Archived from the original on 2012-03-27. Retrieved 2011-09-16.
  15. ^ "Carbfix project – from gas to rock - GREBE Project". GREBE project, European Union. 2017-02-19. Retrieved 2017-12-04.
  16. ^ Sigfusson, Bergur; Gíslason, Sigurður R.; Matter, Juerg M.; Stute, Martin; Gunnlaugsson, Einar; Gunnarsson, Ingvi; Aradóttir, Edda S.; Sigurðardóttir, Holmfriður; Mesfin, Kiflom; Alfredsson, Helgi A.; Wolff-Beonisch, Domenik; Arnarsson, Magnus T.; Oelkers, Eric H. (June 2015). "Solving the carbon-dioxide buoyancy challenge: The design and field testing of a dissolved CO2 injection system". International Journal of Greenhouse Gas Control. 37: 213–219. doi:10.1016/j.ijggc.2015.02.022.2 injection system&rft.volume=37&rft.pages=213-219&rft.date=2015-06&rft_id=info:doi/10.1016/j.ijggc.2015.02.022&rft.aulast=Sigfusson&rft.aufirst=Bergur&rft.au=Gíslason, Sigurður R.&rft.au=Matter, Juerg M.&rft.au=Stute, Martin&rft.au=Gunnlaugsson, Einar&rft.au=Gunnarsson, Ingvi&rft.au=Aradóttir, Edda S.&rft.au=Sigurðardóttir, Holmfriður&rft.au=Mesfin, Kiflom&rft.au=Alfredsson, Helgi A.&rft.au=Wolff-Beonisch, Domenik&rft.au=Arnarsson, Magnus T.&rft.au=Oelkers, Eric H.&rft_id=https://doi.org/10.1016%2Fj.ijggc.2015.02.022&rfr_id=info:sid/en.wikipedia.org:Carbfix" class="Z3988">
  17. ^ "This startup has unlocked a novel way to capture carbon—by turning the dirty gas into rocks". Fortune. Retrieved 2021-12-01.
  18. ^ "Vatnsdæling veldur skjálftum [English: Water pumping causes tremor]". RÚV. 2011-09-13. Retrieved 2024-06-05.
  19. ^ Juncu, D.; Árnadóttir, Th.; Geirsson, H.; Guðmundsson, G.B.; Lund, B.; Gunnarsson, G.; Hooper, A.; Hreinsdóttir, S.; Michalczewska, K. (February 2020). "Injection-induced surface deformation and seismicity at the Hellisheidi geothermal field, Iceland". Journal of Volcanology and Geothermal Research. 391: 106337. Bibcode:2020JVGR..39106337J. doi:10.1016/j.jvolgeores.2018.03.019. ISSN 0377-0273.
  20. ^ Thorsteinsson, H.; Gunnarsson, G. (January 2014). "Induced seismicity-stakeholder engagement in Iceland". GRC Trans. 38, 879–882.
  21. ^ Pind Aradóttir, Edda Sif; Hjálmarsson, Eiríkur (July 2018). "CarbFix – public engagement and transparency". Energy Procedia. 146: 115–120. Bibcode:2018EnPro.146..115P. doi:10.1016/j.egypro.2018.07.015. ISSN 1876-6102.
  22. ^ Snæbjörnsdóttir, Sandra Ó.; Tómasdóttir, Sigrún; Sigfússon, Bergur; Aradóttir, Edda Sif; Gunnarsson, Gunnar; Niemi, Auli; Basirat, Farzad; Dessirier, Benoît; Gislason, Sigurdur R.; Oelkers, Eric H.; Franzson, Hjalti (July 2018). "The geology and hydrology of the CarbFix2 site, SW-Iceland". Energy Procedia. 146: 146–157. Bibcode:2018EnPro.146..146S. doi:10.1016/j.egypro.2018.07.019. ISSN 1876-6102.
  23. ^ Hjörleifsdóttir, Vala; Ingvarsson, Garðar; Ratouis, Thomas; Gunnarsson, Gunnar; Snæbjörnsdóttir, Sandra Ósk; Sigfússon, Bergur (December 2021). "Ten years of induced earthquakes in the Húsmúli CO2 injection site, Hellisheiði, Iceland". Sixth International Conference on Engineering Geophysics, Virtual, 25–28 October 2021. Society of Exploration Geophysicists. pp. 96–100. doi:10.1190/iceg2021-027.1. {{cite book}}: |journal= ignored (help)
  24. ^ "Carbfix". carbfix.com. Retrieved 2024-05-29.
  25. ^ Ratouis, Thomas M.P.; Snæbjörnsdóttir, Sandra Ó.; Voigt, Martin J.; Sigfússon, Bergur; Gunnarsson, Gunnar; Aradóttir, Edda S.; Hjörleifsdóttir, Vala (February 2022). "Carbfix 2: A transport model of long-term CO2 and H2S injection into basaltic rocks at Hellisheidi, SW-Iceland". International Journal of Greenhouse Gas Control. 114: 103586. doi:10.1016/j.ijggc.2022.103586. ISSN 1750-5836.
  26. ^ Clark, Deirdre E.; Oelkers, Eric H.; Gunnarsson, Ingvi; Sigfússon, Bergur; Snæbjörnsdóttir, Sandra Ó.; Aradóttir, Edda S.; Gíslason, Sigurður R. (June 2020). "CarbFix2: CO2 and H2S mineralization during 3.5 years of continuous injection into basaltic rocks at more than 250 °C". Geochimica et Cosmochimica Acta. 279: 45–66. doi:10.1016/j.gca.2020.03.039. hdl:20.500.11815/1757. ISSN 0016-7037.
  27. ^ "Silverstone: mimicking nature's way to transform CO2 into stone - European Commission". cinea.ec.europa.eu. Retrieved 2024-05-29.
  28. ^ "Geothermal Emission Control | GECO Project | Fact Sheet | H2020". CORDIS | European Commission. Retrieved 2024-05-29.
  29. ^ Galeczka, Iwona Monika; Stefánsson, Andri; Kleine, Barbara I.; Gunnarsson-Robin, Jóhann; Snæbjörnsdóttir, Sandra Ósk; Sigfússon, Bergur; Gunnarsdóttir, Sveinborg Hlíf; Weisenberger, Tobias B.; Oelkers, Eric H. (March 2022). "A pre-injection assessment of CO2 and H2S mineralization reactions at the Nesjavellir (Iceland) geothermal storage site". International Journal of Greenhouse Gas Control. 115: 103610. doi:10.1016/j.ijggc.2022.103610. ISSN 1750-5836.
  30. ^ "Upscaling and optimizing subsurface, in situ carbon mineralization as an economically viable industrial option | CarbFix2 Project | Fact Sheet | H2020". CORDIS | European Commission. Retrieved 2024-05-29.
  31. ^ Gutknecht, Valentin; Snæbjörnsdóttir, Sandra Ósk; Sigfússon, Bergur; Aradóttir, Edda Sif; Charles, Louise (July 2018). "Creating a carbon dioxide removal solution by combining rapid mineralization of CO2 with direct air capture". Energy Procedia. 146: 129–134. doi:10.1016/j.egypro.2018.07.017. ISSN 1876-6102.
  32. ^ "Orca is Climeworks' new large-scale carbon dioxide removal plant". Climeworks. Retrieved 2024-05-29.
  33. ^ "Mammoth: our newest direct air capture and storage facility". Climeworks. Retrieved 2024-05-29.
  34. ^ Calma, Justine (2022-06-29). "Construction begins on "Mammoth" direct air capture plant". The Verge. Retrieved 2024-05-29.
  35. ^ "First CO2 transport arrived in Iceland". 2024-05-29.
  36. ^ "About DemoUpCARMA". 2024-05-29.
  37. ^ Becattini, Viola; Wiemer, Stefan; Mazzotti, Marco (April 2024). "Accelerating the climate transition through scientist-led CO2 management pilot projects". Nature Chemical Engineering. 1 (4): 267–269. doi:10.1038/s44286-024-00056-y. ISSN 2948-1198.
  38. ^ "CO2-Seastone". www.carbfix.com. Retrieved 2024-05-29.
  39. ^ "Coda Terminal" (PDF). Retrieved 2024-05-29.
  40. ^ "Carbfix's Coda Terminal awarded large EU grant". www.carbfix.com. Retrieved 2024-05-29.
  41. ^ "Coda Terminal". www.carbfix.com. Retrieved 2024-05-29.
edit