Geochemical characterization of geothermal systems in western Anatolia (Turkey): implications for CO2 trapping mechanisms in prospective CO2-EGS sites

2018-02-01
Geological storage of CO2 is currently regarded as one of the major strategies to mitigate the increasing CO2 concentrations in the atmosphere due to anthropogenic emissions from large-scale point sources. Enhanced geothermal systems (EGS) are a novel concept in which CO2 is used as a working fluid to increase energy recovery, combined with its subsurface storage. In this study, the geothermal systems of western Anatolia are considered as potential sites for EGS, and the published hydrogeochemical data relevant to these systems are compiled and evaluated in terms of potential water/CO2/rock interaction processes. The evaluation is performed with geochemical approaches including speciation-solubility calculations, and inverse and dedolomitization modelling. The results lead to the recognition of two different groups with respect to the effective processes: carbonate precipitation, and carbonate precipitation plus dissolution. In high-enthalpy fields, carbonate precipitation seems to be the major mechanism, while others show the effects of both precipitation and dissolution; dedolomitization is also identified as a potential mechanism for one of the fields. These processes are examined with regard to CO2-fixation; carbonate precipitation may lead to mineral trapping while carbonate dissolution provides additional cations to the system to react with CO2. Being relevant to CO2 storage in geothermal fields, the conclusions from this study point to the importance of temperature control for CO2 stabilization, as high temperatures seem to promote mineral trapping. The success of a CO2-EGS project depends on complete geochemical characterization of reservoir processes with further kinetic modelling accompanying the thermodynamic modelling exemplified by this study. (c) 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.
GREENHOUSE GASES-SCIENCE AND TECHNOLOGY

Suggestions

Geochemical modeling of CO2-water-rock interaction in indonesian geothermal fields for a possible future carbon capture and storage project
Utomo, Gagas Pambudi; Yılmaz, Koray K.; Department of Geological Engineering (2019)
The rise of CO2 concentration in Earth’s atmosphere from anthropogenic emissions is the main cause of global warming and climate change. Carbon Capture and Storage (CCS) is considered as an effective method to reduce such emission. CCS can be performed in various sites including geothermal reservoirs. This study is concerned with geochemical modeling of CO2-water-rock interaction for a possible future CCS project in Indonesian geothermal fields, namely Ungaran, Baturaden, Dieng and Awibengkok. The modeling ...
Geochemical characterization of geothermal systems in Turkey as natural analogues for geological storage of Co2/
Elidemir, Sanem; Güleç, Nilgün Türkan; Department of Geological Engineering (2014)
To mitigate the unfavourable effect of CO2 emission on global warming and climate change, geological storage of CO2 is currently regarded to be one of the major strategies. Deep saline formations constitute one of the alternative reservoirs for hosting the injected CO2 and the information about the behaviour of these reservoirs is provided via the studies of natural analogues. This thesis is concerned with the geothermal systems of Turkey as natural analogues for CO2 storage sites and the evaluation of thei...
Seismic velocity characterisation and survey design to assess CO2 injection performance at Kizildere geothermal field
Parlaktuna, Mahmut; Parlaktuna, Burak; Sınayuç, Çağlar; Senturk, Erdinc; Tonguc, Erinc; Demircioglu, Oncu; Poletto, Flavio; Bohm, Gualtiero; Bellezza, Cinzia; Farina, Biancamaria (2021-08-01)
The noncondensable gases in most geothermal resources include CO2 and smaller amounts of other gases. Currently, the worldwide geothermal power is a small sector within the energy industry, and CO2 emissions related to the utilisation of geothermal resources are consequently small. In some countries, however, such as Turkey and Iceland, geothermal energy production contributes significantly to their energy budget, and their CO2 emissions are relatively significant. SUCCEED is a targeted innovation and resea...
CO2 hydrogenation to methanol over supported copper and gallium based catalysts at the atmospheric pressure
Osmanağa, Sezer; İpek Torun, Bahar; Önal, Işık; Department of Chemical Engineering (2022-8)
The continuous increase of the CO2 concentration in the atmosphere has been negatively impacting the environment, due to its contribution in the global warming. Hence, it is necessary for the current CO2 valorization techniques to advance in order to make use of CO2. A possible technique is the CO2 hydrogenation to methanol and DME. The process of CO2 hydrogenation to methanol has been taking place in industry for about a century. However, due to the thermodynamic limitation imposed by the reaction stoichio...
Geothermal systems as natural analogues for geological storage of CO2: implications for trapping mechanisms from hydrogeochemistry of western Anatolian fluids (Turkey).
Elidemir, Sanem; Güleç, Nilgün Türkan (2017-08-13)
Carbon Capture and Storage (CCS) is a widely accepted strategy to reduce the unfavourable effects of CO2 emission on global warming. Natural analogues provide a valuable source for the investigation of the behaviour of CO2 at subsurface after its injection. Geothermal fields, representing deep saline aquifers, are considered as natural analogues for CO2 storage sites. This study focuses on the geothermal systems of western Anatolia (Turkey) to investigate the possible CO2-fixation mechanisms by using the pu...
Citation Formats
S. Elidemir and N. T. Güleç, “Geochemical characterization of geothermal systems in western Anatolia (Turkey): implications for CO2 trapping mechanisms in prospective CO2-EGS sites,” GREENHOUSE GASES-SCIENCE AND TECHNOLOGY, pp. 63–76, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38436.