GLOBAL CCS INSTITUTE
The CarbFix-SulFix Project
Project Proponents
The main partners include Reykjavik Energy, the University of
Iceland, the Earth Institute at the Columbia University and the
National Center for Scientific Research in France.
Location
The Hellisheidi geothermal power station area near Hengill,
southwest Iceland.
Project Status
Ongoing.
CO2 Capture Capacity
Gas mixture from the Hellisheidi geothermal power station – total
CO2 injected by end December 2014 was approximately 2,400
tonnes.
Storage Type
Geological storage – mineral carbonation via injection of dissolved
CO2 gas mixture into reactive basaltic rock (at a depth of around
800 metres or greater).
Project Information
Geothermal energy is a clean energy source, though its utilisation is generally associated with emissions
of geothermal gases, like carbon dioxide (CO2) and hydrogen sulphide (H2S). In Iceland, Reykjavik
Energy and its project partners have been undertaking larger-scale testing of gas mixture re-injection at
the Hellisheidi geothermal power plant, following pilot tests in 2011-2012.
The CarbFix-SulFix project involves re-injecting a gas mixture of approximately 70% CO2 and 30% H2S,
dissolved in water from the Hellisheidi power plant, into basaltic formations, with the purpose of storing the
gases in mineral in the bedrock. Rather than re-injecting CO2 directly into geological formations, the
CarbFix-SulFix project dissolves the gas stream into formation fluids and well water during injection. This
solubility-trapping approach is expected to promote carbonation of the host rock and long-term storage of
the re-injected gas stream.
The initial pilot tests included reinjection tests of a pure CO 2 gas stream sourced from commercial sources
as well as reinjection of the gas mixture from the power plant (for what were often labelled separate
CarbFix and SulFix projects). During the pilot tests around 170 tonnes of pure CO 2 was injected into a
target zone between 400-800 metres (with formation temperature at 30-80°C). Approximately 100 tonnes
of gas mixture was injected into a target zone in excess of 800 metres (with a formation temperature
greater than 200°C).
The initial pilot tests demonstrated solubility storage of the pure gases in a few minutes, and that more
than 80% of the injected CO2 into basaltic rocks was mineralised with 12 months of the injection date (at
formation temperature of 20-50°C).
The ‘larger-scale injection’ CarbFix-SulFix project commenced injection in early June 2014, with injection
of the (dissolved) gas mixture at a depth of approximately 800 metres. Approximately 2,400 tonnes of CO 2
and 1,300 tonnes of H2S had been injected by the end of 2014. Four monitoring wells were used to collect
water and gas samples.
Further information can be accessed from:
Clark, D.E., et al., The CarbFix-SulFix project: Mineral storage of CO2/H2S gas mixtures in basaltic rocks,
Goldschmidt2015 Abstracts, 2015.
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GLOBAL CCS INSTITUTE
The CarbFix-SulFix Project
http://goldschmidt.info/2015/uploads/abstracts/finalPDFs/564.pdf
AradÓttir, E., et al., Carbfix final report, Carbfix Project no. 281348, Seventh Framework Programme,
dated November 2014.
http://cordis.europa.eu/docs/results/283/283148/final1-carbfix-final-report-vff.pdf
AradÓttir, E. and Gunnarsson, I., CarbFix and SulFix sequestration projects, GEORG W2V seminar, May
2013.
http://georg.hi.is/files/CarbFix%20and%20SulFix_GEORG%2008052013.pdf
Gunnarsson, I., et al., Geothermal Gas Emission from Hellisheidi and Nesjavellir Power Plants, Iceland,
GRC Transactions, Vol. 37, 2013.
https://www.or.is/sites/or.is/files/geothermal_gas_emission_from_hellisheidi_and_nesjavellir_power_plant
s.pdf
AradÓttir, E., et al., Towards Cleaner Geothermal Energy Utilisation: Capturing and Sequestering CO 2 and
H2S Emissions: from Geothermal Power Plants, Proceedings, TOUGH Symposium, 2012.
https://zenodo.org/record/12901/files/Edda_S.P._Aradottir_et_al._2012.pdf
Oelkers, E., Carbon Storage in Basalts: The CarbFix Story 2006-2015”, Highlight Seminar, Princeton
University, October 2015.
https://acee.princeton.edu/events/eric-oelkers/
Dated: January 2016
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