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  • 1.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Denchik, Nataliya
    Univ Montpellier 2, Geosci Montpellier CNRS UMR 5243, Cc 060 Bat 22,Pl Eugene Bataillon, F-34095 Montpellier 05, France..
    Pezard, Philippe A.
    Univ Montpellier 2, Geosci Montpellier CNRS UMR 5243, Cc 060 Bat 22,Pl Eugene Bataillon, F-34095 Montpellier 05, France..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Numerical modelling of CO2 injection at small-scale field experimental site in Maguelone, France2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 54, p. 200-210Article in journal (Refereed)
    Abstract [en]

    To evaluate the performance of downhole and surface geophysical monitoring methods, a series of shallow gas injection-monitoring experiments has been performed in a coastal saline aquifer at Maguelone, France. The recorded data include pressure measurements with a Westbay multilevel completion and CO2 saturation at an observation well derived from electrical resistivity with a modified Waxman-Smits (MWS) model. In this work, the aim is to develop a simulation model capturing the gas transport behavior and consistent with field data. For this purpose, the simulation of the CO2 injection experiment is carried out with two conceptual models, a homogeneous model and a heterogeneous model treated with multiple realization Monte Carlo simulations. Numerical simulator TOUGH2 with the equation of state module EOS7C is used for the simulations. Comparison of the model results with field data suggests that the pressure responses are captured with relatively good accuracy. Similarly, the model also provides an overall reasonable agreement and correct order of magnitude for predicted gas saturation values. However, as the heterogeneity pattern in the field data remains largely unknown, the model predictions can only be used to capture the mean behavior as well as to provide insights into how heterogeneity can influence the system behavior, by means of sensitivity analyses of the influence of heterogeneities on individual realizations.

  • 2.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Perroud, Herve
    Universit´e de Montpellier.
    Lofi, Johanna
    Universit´e de Montpellier.
    Denchik, Nataliya
    Universit´e de Montpellier.
    Lods, Gerard
    Universit´e de Montpellier.
    Pezard, Philippe
    Universit´e de Montpellier.
    Fagerlund, Fritjof
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modeling Gas Transport in the Shallow Subsurface in Maguelone Field Experiment2013In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, p. 337-345Article in journal (Refereed)
    Abstract [en]

    In this paper, TOUGH2/EOS7CA model is used to simulate the shallow injection-monitoring experiment carried outat Maguelone, France, during 2012 and 2013. The ultimate objective of the work is to improve our understanding ofgas transport in the shallow subsurface as well as to develop and validate the model to monitor it. This workrepresents first results towards modelling the nitrogen and CO2 injection experiments carried out. The pressure datafrom the first injection experiments in summer 2012 is used as basis for comparison. Work is presently going on toincorporate the experimental data into the numerical simulation further.

  • 3.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Experimental and modeling investigation of CO2 flow and transport in a coupled domain of porous media and free flow2015In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 42, p. 461-470Article in journal (Refereed)
    Abstract [en]

    A solid understanding of the transport mechanisms of gaseous CO2 near the land surface is necessary for developing reliable monitoring techniques and predictive models for possible CO2 leakage from deep underground storage. The objective of this work has been to develop an experimental method along with a simulation model for gaseous CO2 flow and transport in a system including both the porous media and the free air space above it. The experimental system consisted of a two-dimensional bench scale rectangular sandbox containing homogenous sand with an open space of still air above it. Gaseous CO2 was injected in different modes and the CO2 breakthrough was measured on specified ports in the system by using CO2 concentration sensors. A numerical model combining the gas flow in the porous medium and the free flow region was developed and used to model the experimental data. In this quest, the Discontinuous One-Domain approach was selected for modeling transport between the free flow and porous regions. The observed and simulated CO2 breakthrough curves both in the dried sand and in the free flow matched very well in the case of uniform injection and satisfactorily even in the case of point injection. Consequently, it seems that the model reasonably matches the observed data in the cases where the boundary condition is well defined. In summary, our results show that the developed experimental setup provides capability to study gaseous CO2 flow and transport in a coupled porous medium - free flow system and that our modeling approach is able to predict the flow and transport in this system with good accuracy.

  • 4.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Pore-scale modeling of wettability effects on CO2–brine displacement during geological storage2017In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 109, p. 181-195Article in journal (Refereed)
    Abstract [en]

    Wetting properties of reservoir rocks and caprocks can vary significantly, and they strongly influence geological storage of carbon dioxide in deep saline aquifers, during which CO2 is supposed to displace the resident brine and to become permanently trapped. Fundamental understanding of the effect of wettability on CO2-brine displacement is thus important for improving storage efficiency and security. In this study, we investigate the influence of wetting properties on two-phase flow of CO2 and brine at the pore scale. A numerical model based on the phase field method is implemented to simulate the two-phase flow of CO2-brine in a realistic pore geometry. Our focus is to study the pore-scale fluid-fluid displacement mechanisms under different wetting conditions and to quantify the effect of wettability on macroscopic parameters such as residual brine saturation, capillary pressure, relative permeability, and specific interfacial area. Our simulation results confirm that both the trapped wetting phase saturation and the normalized interfacial area increase with decreasing contact angle. However, the wetting condition does not appear to influence the CO2 breakthrough time and saturation. We also show that the macroscopic capillary pressures based on the pressure difference between inlet and outlet can differ significantly from the phase averaging capillary pressures for all contact angles when the capillary number is high ( log Ca > -5). This indicates that the inlet-outlet pressure difference may not be a good measure of the continuum-scale capillary pressure. In addition, the results show that the relative permeability of CO2 can be significantly lower in strongly water-wet conditions than in the intermediate-wet conditions.

  • 5.
    Bensabat, Jacob
    et al.
    Environmental & water resources engineering Ltd (EWRE), Haifa, Israel.
    Kitron-Belinkov, Myra
    Technion - Israel Institute of Technology, Deptartment of Civil, Environmental and Water Resources engineering, Haifa, Israel.
    Rasmusson, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Rasmusson, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bear, Jacob
    Technion - Israel Institute of Technology, Department of Civil, Environmental and Water Resources engineering, Haifa, Israel.
    Model for the dependence of conditions at the injection well head and the reservoir during CO2 injection2011Conference paper (Refereed)
    Abstract [en]

    Highly controlled field injection experiments are necessary for demonstration, for scientific understanding and for quantification of the relevant processes of CO2 geological storage.

    The preparation of such an experiment requires reliable information on both the hydraulic, thermal and chemical properties of the target layer and the formation fluid as well as on the injection discharges and their associated pressure build-up in the reservoir. For this, there is a need to determine the state variables of CO2 in the injection tube near the well head, which can produce the desired mass flow rates given the condition at the reservoir, while respecting pressure buildup constraints.

     

    A model connecting the multiphase flow and transport processes in the target layer (based on the well-known TOUGH2/ECO2N model) at the vicinity of the injection well with those occurring in the injection tube (solving the one dimensional equations mass, momentum and energy conservation) has been developed. To this model the injection tube is a boundary condition. Once the reservoir pressure build-up resulting from the injection discharge is known, there is a need to determine the necessary injection conditions at the wellhead. For this purpose we apply the 1-D tube model, which provides the solution of the conditions in the injection pipe, given the injection rate and the pressure at the reservoir.

     

    These two linked models, the porous medium model and the pipe model, are applied to the planning of the Heletz injection experiment to be carried out in the frame of the EU-FP7 funded MUSTANG project. Sensitivity analyses are carried out with regard to uncertainty in the target layer permeability and the temperature of the injected CO2, which depends on the thermal heat transfer coefficient in the injection tube.

  • 6.
    Bockgård, Niclas
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Niemi, Auli
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Role of rock heterogeneity on lateral diversion of water flow at the soil-rock interface2004In: Vadose Zone Journal, ISSN 1539-1663, Vol. 3, no 3, p. 786-795Article in journal (Refereed)
  • 7.
    Brown, Solomon
    et al.
    UCL, Sch Chem Engn, London WC1E 7JE, England..
    Martynov, Sergey
    UCL, Sch Chem Engn, London WC1E 7JE, England..
    Mahgerefteh, Haroun
    UCL, Sch Chem Engn, London WC1E 7JE, England..
    Fairweather, Michael
    Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Woolley, Robert M.
    Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Wareing, Christopher J.
    Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Falle, Samuel A. E. G.
    Univ Leeds, Sch Math, Leeds LS2 9JT, W Yorkshire, England..
    Rutters, Heike
    Bundesanstalt Geowissensch & Rohstoffe, D-30655 Hannover, Germany..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Zhang, Yong Chun
    Dalian Univ Technol, Dalian, Peoples R China..
    Chen, Shaoyn
    Dalian Univ Technol, Dalian, Peoples R China..
    Besnebat, Jacob
    Environm & Water Resources Engn Ltd, IL-34641 Heifa, Israel..
    Shah, Nilay
    Imperial Coll London, Ctr Environm Policy, London, England..
    Mac Dowell, Niall
    Imperial Coll London, Ctr Environm Policy, London, England..
    Proust, Christophe
    INERIS, F-60550 Paris, France..
    Farret, Regis
    INERIS, F-60550 Paris, France..
    Economou, Ioannis G.
    Natl Ctr Sci Res Demokritos, GR-15310 Attikis, Greece..
    Tsangaris, Dimitrios M.
    Natl Ctr Sci Res Demokritos, GR-15310 Attikis, Greece..
    Boulougouris, Georgios C.
    Natl Ctr Sci Res Demokritos, GR-15310 Attikis, Greece..
    Van Wittenberghe, Jeroen
    ArcelorMittal, OCAS NV, B-9060 Zelzate, Belgium..
    CO(2)QUEST: Techno-economic assessment of CO2 quality effect on its storage and transport2014In: 12TH INTERNATIONAL CONFERENCE ON GREENHOUSE GAS CONTROL TECHNOLOGIES, GHGT-12, 2014, p. 2622-2629Conference paper (Refereed)
    Abstract [en]

    Presented is an overview of the CO(2)QUEST project that addresses fundamentally important issues regarding the impact of typical impurities in the gas or dense phase CO2 stream captured from fossil fuel power plants on its safe and economic transportation and storage. Previous studies have mainly investigated the impact of CO2 stream impurities on each part of the carbon capture and storage (CCS) chain in isolation. This is a significant drawback given the different sensitivities of pipeline, wellbore materials and storage sites to the various impurities. The project brings together leading researchers and stakeholders, to address the impact of the typical impurities upon safe and economic CO2 transportation and storage. State-of-the-art mathematical models, backed by laboratory and industrial-scale experimentation, are implemented to perform a comprehensive techno-economic assessment of the impact of impurities upon the thermo-physical phenomena governing pipeline and storage-site integrities.

  • 8.
    Dessirier, Benoît
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A new scripting library for modeling flow and transport in fractured rock with channel networks2018In: Computers & Geosciences, ISSN 0098-3004, E-ISSN 1873-7803, Vol. 111, p. 181-189Article in journal (Refereed)
    Abstract [en]

    Deep crystalline bedrock formations are targeted to host spent nuclear fuel owing to their overall low permeability. They are however highly heterogeneous and only a few preferential paths pertaining to a small set of dominant rock fractures usually carry most of the flow or mass fluxes, a behavior known as channeling that needs to be accounted for in the performance assessment of repositories. Channel network models have been developed and used to investigate the effect of channeling. They are usually simpler than discrete fracture networks based on rock fracture mappings and rely on idealized full or sparsely populated lattices of channels. This study reexamines the minimal requirements to describe a channel network in terms of groundwater flow and solute transport, leading to an extended description suitable for unstructured arbitrary networks of channels. An implementation of this formalism in a Python scripting library is presented and released along with this article. A new algebraic multigrid preconditioner delivers a significant speedup in the flow solution step compared to previous channel network codes. 3D visualization is readily available for verification and interpretation of the results by exporting the results to an open and free dedicated software. The new code is applied to three example cases to verify its results on full uncorrelated lattices of channels, sparsely populated percolation lattices and to exemplify the use of unstructured networks to accommodate knowledge on local rock fractures.

  • 9.
    Dessirier, Benoît
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A new scripting library for modeling flow and transport in fractured rock with channel networks2018In: Computers & Geosciences, ISSN 0098-3004, E-ISSN 1873-7803, Vol. 111, p. 181-189Article in journal (Refereed)
    Abstract [en]

    Deep crystalline bedrock formations are targeted to host spent nuclear fuel owing to their overall low permeability. They are however highly heterogeneous and only a few preferential paths pertaining to a small set of dominant rock fractures usually carry most of the flow or mass fluxes, a behavior known as channeling that needs to be accounted for in the performance assessment of repositories. Channel network models have been developed and used to investigate the effect of channeling. They are usually simpler than discrete fracture networks based on rock fracture mappings and rely on idealized full or sparsely populated lattices of channels. This study reexamines the fundamental parameter structure required to describe a channel network in terms of groundwater flow and solute transport, leading to an extended description suitable for unstructured arbitrary networks of channels. An implementation of this formalism in a Python scripting library is presented and released along with this article. A new algebraic multigrid preconditioner delivers a significant speedup in the flow solution step compared to previous channel network codes. 3D visualization is readily available for verification and interpretation of the results by exporting the results to an open and free dedicated software. The new code is applied to three example cases to verify its results on full uncorrelated lattices of channels, sparsely populated percolation lattices and to exemplify the use of unstructured networks to accommodate knowledge on local rock fractures.

  • 10.
    Edlmann, K.
    et al.
    Univ Edinburgh, Sch Geosci, Grant Inst, James Hutton Rd, Edinburgh EH93FE, Midlothian, Scotland..
    Bensabat, J.
    EWRE, Haifa, Israel..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Haszeldine, R. S.
    Univ Edinburgh, Sch Geosci, Grant Inst, James Hutton Rd, Edinburgh EH93FE, Midlothian, Scotland..
    McDermott, C. I.
    Univ Edinburgh, Sch Geosci, Grant Inst, James Hutton Rd, Edinburgh EH93FE, Midlothian, Scotland..
    Lessons learned from using expert elicitation to identify, assess and rank the potential leakage scenarios at the Heletz pilot CO2 injection site2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 49, p. 473-487Article in journal (Refereed)
    Abstract [en]

    Expert elicitation is a useful approach to synthesis expert knowledge, experience and insight when the input data and analysis is limited. During the early stages of the EU FP7 MUSTANG pilot CO2 injection experiment at Heletz, Israel there was very little input data available, yet decisions had to be made regarding data collection, drilling, operation and monitoring strategies. An expert elicitation study was undertaken to identify, assess and rank potential CO2 leakage scenarios at Heletz to provide guidance to support the decision making processes. This paper presents a critique of the expert elicitation process undertaken, presenting the methodology and a discussion of the results. We present the lessons learned during the expert elicitation process, highlighting its advantages and limitations and provide suggestions on ways to overcome these limitations. Our findings show that prudent expert elicitation can make a valuable contribution to decision making, however if done improperly it can equally lead to invalid or misleading results and wrong decisions.

  • 11.
    Edlmann, K.
    et al.
    Univ Edinburgh, Grant Inst, Sch Geosci, Kings Bldg,James Hutton Rd, Edinburgh EH9 3FE, Midlothian, Scotland..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, J.
    EWRE, Haifa, Israel..
    Haszeldine, R. S.
    Univ Edinburgh, Grant Inst, Sch Geosci, Kings Bldg,James Hutton Rd, Edinburgh EH9 3FE, Midlothian, Scotland..
    McDermott, C. I.
    Univ Edinburgh, Grant Inst, Sch Geosci, Kings Bldg,James Hutton Rd, Edinburgh EH9 3FE, Midlothian, Scotland..
    Mineralogical properties of the caprock and reservoir sandstone of the Heletz field scale experimental CO2 injection site, Israel; and their initial sensitivity to CO2 injection2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 48, p. 94-104Article in journal (Refereed)
    Abstract [en]

    This paper presents the initial database of the mineralogy of the caprock and reservoir sandstones of the Heletz field scale experimental CO2 injection site, Israel. The XRD mineralogy results show that the Heletz caprock has K-feldspar as the primary mineral (40%) followed by kaolinite (15%) and plagioclase feldspar (12%) then illite (6%) and muscovite (6%) with minor quartz, calcite, pyrite, chlorite and ankerite with traces of siderite. The Heletz reservoir rock is primarily quartz (70%) followed by K-feldspar (12%) and plagioclase feldspar (4%) with minor illite, kaolinite, muscovite, chlorite ankerite and pyrite with traces of dolomite, calcite and siderite. "Cook and look" bench experiments were conducted on the Heletz caprock and reservoir sandstone samples to identify if there was any immediate mineral reactivity that would influence permeability on exposure to CO2 that may cause concerns during well completion and initial injection of CO2 at Heletz. The sandstone exhibited reactivity under brine dis-equilibrium which was observed in the field with loss of injectivity which was restored by injecting KCL into the well and performing 20 swab-suctions. The caprock revealed no reactivity of immediate concern to the well completion and injection strategy and will retain its integrity.

  • 12.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Hellman, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Målqvist, Axel
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Improved Monte Carlo methods for computing failure probabilities of porous media flow systems2015Report (Other academic)
  • 13.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Hellman, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Målqvist, Axel
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Multilevel Monte Carlo methods for computing failure probability of porous media flow systems2016In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 94, p. 498-509Article in journal (Refereed)
  • 14.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Illangasekare, Tissa H.
    Center for Experimental Study of Subsurface Environmental Processes (CESEP), Environmental Science and Engineering, Colorado School of Mines, Golden, CO.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Nonaqueous-phase liquid infiltration and immobilization in heterogeneous media: 1. Experimental methods and two-layered reference case2007In: Vadose Zone Journal, ISSN 1539-1663, E-ISSN 1539-1663, Vol. 6, no 3, p. 471-482Article in journal (Refereed)
    Abstract [en]

    Accurate data to understand the migration and entrapment ofnonaqueous-phase liquids (NAPLs) in heterogeneous formationsare presently lacking. A series of well-controlled laboratoryexperiments were conducted to investigate the infiltration andsubsequent immobilization of dense NAPLs in saturated heterogeneousmedia. The focus of this first study was the development ofa special experimental methodology for measuring the dynamicevolution of a NAPL plume in space and time. To demonstratethe method, a reference case of a two-layered formation consistingof two homogeneous sands separated by a dipping interface ispresented. The dipping formation in the reference case allowsthe study of NAPL behavior at texture interfaces under the influenceof both capillary and gravitational forces. The NAPL-saturationmeasurement methodology, based on a multiple-energy x-ray attenuationtechnique, correctly captured the known injected NAPL volumeas well as the general spreading and entrapment behavior inspace and time. Time-continuous measurements of NAPL saturationsallow the study of the history dependence of entrapped saturations.The Land model predicted the observed trend in the entrapmentbehavior well. The entrapment architecture was parameterizedusing spatial moments and moments of mass distribution at differentsaturations. The general features of the NAPL architecture weresuccessfully characterized by a simultaneous interpretationof these moments, while the domination of discontinuous or continuousNAPL was captured by the ganglia/pool ratio.

  • 15.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Illangasekare, Tissa H.
    Center for Experimental Study of Subsurface Environmental Processes (CESEP), Environmental Science and Engineering, Colorado School of Mines, Golden, Colorado, USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Nonaqueous-phase liquid infiltration and immobilization in heterogeneous media: 2. Application to stochastically heterogeneous formations2007In: Vadose Zone Journal, ISSN 1539-1663, E-ISSN 1539-1663, Vol. 6, no 3, p. 483-495Article in journal (Refereed)
    Abstract [en]

    We performed a series of well-controlled laboratory experimentsinvestigating the infiltration and subsequent immobilizationof nonaqueous-phase liquid (NAPL) in saturated heterogeneousmedia. A system of two distinct aquifer zones separated by adipping interface was considered. Heterogeneity was representedby a spatially correlated random field with known geostatisticalparameters in one zone in combination with a homogenous packingof the other zone. The effects of heterogeneity on NAPL flowand entrapment in each of the two zones were investigated. Thetime-varying NAPL saturations were continuously monitored inspace and the final static entrapment–saturation distributionwas accurately measured. The immobilized-NAPL distribution contributesto plume generation from source zones. The results show thatcapillary barriers produced by the small-scale heterogeneitystrongly influenced the migration paths and the final distributionof NAPL both in space and across different saturation ranges.The NAPL was immobilized both by snap-off to discontinuous blobsand ganglia and by capillary barriers at textural interfaces.Heterogeneity generally increased entrapment, because spatialvariations in capillary properties caused NAPL to be entrappedat higher saturations. Heterogeneity in the finer formationprovided points of entry into this formation where the NAPLsubsequently could spread as the pressure built up. The NAPLwas immobilized at high saturations because high displacementpressures in the fine materials inhibited flow at low saturations.The accessibility for water flow through NAPL occurrences andthereby also the dissolution of NAPL is limited by (i) highentrapped NAPL saturations that decrease the aqueous-phase relativepermeability and (ii) the location of NAPL inside a formationwith low average permeability.

  • 16.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    A partially coupled, fraction-by-fraction modelling approach to the subsurface migration of gasoline spills2007In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009, Vol. 89, no 3-4, p. 174-198Article in journal (Refereed)
    Abstract [en]

    The subsurface spreading behaviour of gasoline, as well as several other common soil- and groundwater pollutants (e.g. diesel, creosote), is complicated by the fact that it is a mixture of hundreds of different constituents, behaving differently with respect to e.g. dissolution, volatilisation, adsorption and biodegradation. Especially for scenarios where the non-aqueous phase liquid (NAPL) phase is highly mobile, such as for sudden spills in connection with accidents, it is necessary to simultaneously analyse the migration of the NAPL and its individual components in order to assess risks and environmental impacts.

    Although a few fully coupled, multi-phase, multi-constituent models exist, such models are highly complex and may be time consuming to use. A new, somewhat simplified methodology for modelling the subsurface migration of gasoline while taking its multi-constituent nature into account is therefore introduced here. Constituents with similar properties are grouped together into eight fractions. The migration of each fraction in the aqueous and gaseous phases as well as adsorption is modelled separately using a single-constituent multi-phase flow model, while the movement of the free-phase gasoline is essentially the same for all fractions. The modelling is done stepwise to allow updating of the free-phase gasoline composition at certain time intervals. The output is the concentration of the eight different fractions in the aqueous, gaseous, free gasoline and solid phases with time.

    The approach is evaluated by comparing it to a fully coupled multi-phase, multi-constituent numerical simulator in the modelling of a typical accident-type spill scenario, based on a tanker accident in northern Sweden. Here the PCFF method produces results similar to those of the more sophisticated, fully coupled model. The benefit of the method is that it is easy to use and can be applied to any single-constituent multi-phase numerical simulator, which in turn may have different strengths in incorporating various processes. The results demonstrate that the different fractions have significantly different migration behaviours and although the methodology involves some simplifications, it is a considerable improvement compared to modelling the gasoline constituents completely individually or as one single mixture.

  • 17.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    EWRE.
    Rasmusson, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Rasmusson, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tian, Liang
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Shtivelman, Vladimir
    GII.
    Licha, Tobias
    Applied Geology, University of Göttingen, Germany.
    Design and Analysis of Field Experiments for the Investigation of In-Situ CO2 Trapping2010In: 2010 Fall Meeting, American Geophysical Union (AGU): Abstract H13C-0981, 2010Conference paper (Other academic)
  • 18.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    Shtivelman, Vladimir
    Design of a two-well field test to determine in situ residual and dissolution trapping of CO2 applied to the Heletz CO2 injection site2013In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 19, p. 642-651Article in journal (Refereed)
    Abstract [en]

    Field testing is a critical step to improve our knowledge on in situ-trapping mechanisms of CO2 injected in geological formations and their relative importance. In this study, we present a two-well test sequence aimed at quantifying field values of both residual and dissolution trapping of CO2. Then, we apply it to the Heletz experimental CO2 injection site, using numerical modelling. The sequence includes a hydraulic test to measure residual scCO(2) saturation and a novel tracer technique, together with measurements of abstracted fluid compositions for quantification of the rate of CO2 dissolution in the reservoir. The proposed tracer technique uses a tracer with negligible aqueous solubility, which is injected with the scCO(2) and enriched in the scCO(2) phase as CO2 dissolves. We show that this tracer can provide direct information about the dissolution of mobile scCO(2). We also show that the rate of abstracted dissolved CO2 can be used to predict the total rate of CO2 dissolution, provided that the amount of dissolved CO2 in the formation stabilizes, and that this can be achieved with the proposed abstraction scheme. We conclude that the combination of these measurements is a promising tool for detailed field-scale characterization of residual and dissolution trapping processes.

  • 19.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    EWRE.
    Shtivelman, Vladimir
    GII.
    Evaluation of design options for a field experiment of CO2 injection to a deep layered aquifer at the Heletz site using numerical modelling2011In: Geophysical Research Abstracts Vol. 13: EGU2011-7291, 2011Conference paper (Other academic)
  • 20.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    Shtivelman, Vladimir
    Interwell field test to determine in-situ CO2 trapping in a deep saline aquifer: Modelling study of the effects of test design and geological parameters2013In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 40, p. 554-563Article in journal (Refereed)
    Abstract [en]

    An interwell field test to determine residual phase and dissolution trapping of CO2 is being designed at Heletz, Israel. Effects of test-design options and geological parameters were investigated using numerical modelling. It was found that the interwell distance has large influence on the feasibility of the test both in terms of creation of a zone of residually trapped CO2 and detection of the time when such zone has been created. The optimal distance is site-specific and depends on formation properties. Alternating CO2 and brine injections slightly increased residual trapping, but did not facilitate creation of a well-defined zone of trapping.

  • 21.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    EWRE.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Shtivelman, Vladimir
    GII.
    Goldberg, I
    GII.
    Simulations of CO2 injection at the Heletz field site – providing guidance for optimal design of a planned field injection experiment2009In: Eos Trans. AGU, 90(52), Fall Meet. Suppl.: Abstract H13A-0921, 2009Conference paper (Other academic)
  • 22.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    EWRE.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Shtivelman, Vladimir
    GII.
    Goldberg, I
    GII.
    Gendler, M
    GII.
    Model simulations for guiding the design of the CO2 injection experiment at the Heletz site2010In: Geophysical Research Abstracts Vol. 12: EGU2010-13147, 2010Conference paper (Other academic)
  • 23.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    EWRE.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Shtivelman, Vladimir
    GII.
    Goldberg, I
    GII.
    Gendler, M
    GII.
    Modeling CO2 injection to aid the design of a field experiment at the Heletz site2010Conference paper (Other academic)
  • 24.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Illangasekare, Tissa
    Center for Experimental Study of Subsurface Environmental Processes, Department of Environmental Science and Engineering, Colorado School of Mines, Golden, Colorado, USA. .
    Modeling of nonaqueous phase liquid (NAPL) migration in heterogeneous saturated media: Effects of hysteresis and fluid immobility in constitutive relations2008In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 44, no 3, article id W03409Article in journal (Refereed)
    Abstract [en]

    The confidence in model predictions for nonaqueous phase liquid (NAPL) transport in stochastically heterogeneous systems is limited. The fundamental approaches as well as the constitutive models have not been sufficiently validated, mainly because of the lack of appropriate experimental data. Recently, Fagerlund et al. (2007a, 2007b) presented a set of well-controlled laboratory data that are used here (1) to analyze the overall performance of the continuum-based approach for predicting two-phase NAPL-water flow in stochastically heterogeneous media and (2) to compare the predictions from different constitutive models. The five models tested were the nonhysteretic Brooks-Corey-Burdine (BCB) and van Genuchten-Mualem (VGM) models, the hysteretic versions of these models (HBCB and HVGM), and the HVGBCB model, a model combining the hysteretic van Genuchten (HVG) P c -S relation and the hysteretic Brooks-Corey-Burdine k r -S relation. Two cases of NAPL migration were considered: a layered system of two homogeneous sands separated by a dipping interface and a system where one of the layers was stochastically heterogeneous. The results showed that the best models could indeed capture the main characteristics of the spreading and immobilization well, demonstrating the validity of the continuum-based approach for this level of stochastic heterogeneity. Implementation of hysteresis was necessary for correct prediction of the observed speed of NAPL migration as well as the amount of immobilized NAPL. The three hysteretic models were similar in their overall prediction error-based performance. The HVGM model produced less overestimation of NAPL saturations but instead underestimated the entrapment at capillary barriers in comparison to the HBCB and HVGBCB models. The HVGM model also overestimated the speed of NAPL migration, which is attributed to its closed-form k r -S function, for which the VG parameter m has to be fitted under the constraint m = 1 − 1/n. The HVG (and VG) P c -S function, in contrast, used a different set of VG parameters produced with no constraint on m, which better represented the pore size distributions of the sands. A relation for partial nonwetting phase immobility during drainage is also presented.

  • 25.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tong, Fuguo
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Licha, Tobias
    Applied Geology, University of Göttingen, Germany.
    Sauter, Martin
    Applied Geology, University of Göttingen, Germany.
    Modelling of novel tracers in a two-phase flow system for characterization of geologically stored CO2 in deep saline formations2011In: Geophysical Research Abstracts Vol. 13: EGU2011-11814, 2011Conference paper (Other academic)
  • 26.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley National Laboratory, Berkeley USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Georg, Lindgren
    Swedish Radiation Safety Authority, Stockholm, Sweden.
    Review: The state-of-art of sparse channel models and their applicability to performance assessment of radioactive waste repositories in fractured crystalline formations2016In: Hydrogeology Journal, ISSN 1431-2174, E-ISSN 1435-0157, Vol. 24, no 7, p. 1607-1622Article in journal (Other academic)
    Abstract [en]

    Laboratory and field experiments done on fractured rock show that flow and solute transport often occur along flow channels. ‘Sparse channels’ refers to the case where these channels are characterised by flow in long flow paths separated from each other by large spacings relative to the size of flow domain. A literature study is presented that brings together information useful to assess whether a sparse-channel network concept is an appropriate representation of the flow system in tight fractured rock of low transmissivity, such as that around a nuclear waste repository in deep crystalline rocks. A number of observations are made in this review. First, conventional fracture network models may lead to inaccurate results for flow and solute transport in tight fractured rocks. Secondly, a flow dimension of 1, as determined by the analysis of pressure data in well testing, may be indicative of channelised flow, but such interpretation is not unique or definitive. Thirdly, in sparse channels, the percolation may be more influenced by the fracture shape than the fracture size and orientation but further studies are needed. Fourthly, the migration of radionuclides from a waste canister in a repository to the biosphere may be strongly influenced by the type of model used (e.g. discrete fracture network, channel model). Fifthly, the determination of appropriateness of representing an in situ flow system by a sparse-channel network model needs parameters usually neglected in site characterisation, such as the density of channels or fracture intersections.

  • 27.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Rutqvist, Jonny
    Bensabat, Jac
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Coupled hydro-mechanical processes and fault reactivation induced by Co-2 Injection in a three-layer storage formation2015In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 39, p. 432-448Article in journal (Refereed)
    Abstract [en]

    The interaction between mechanical deformation and fluid flow in fault zones gives rise to a host of coupled hydro-mechanical processes fundamental to fault instability, induced seismicity, and associated fluid migration. Fault stability is studied in the context of the Heletz site which was chosen as a test site for CO2 injection experiment in the framework of the EU-MUSTANG project. The potential reservoir for CO2 storage at the Heletz site consists of three sandstone layers that are approximately one, two and nine meters in thickness, separated by impermeable shale layers of various thicknesses, and overlaid by a five-meter limestone and a thick impermeable shale, which serves as caprock. The storage formation is intersected by two pre-existing sub-vertical normal faults (F1 and F2) on two opposite sides of the injection point. A hydro-mechanical model was developed to study the interaction between mechanical deformation and fluid flow in the two faults during CO2 injection and storage. We evaluate the consequences caused by potential fault reactivation, namely, the fault slip and the CO2 leakage through the caprock. The difference in the results obtained by considering the three-layer storage formation as an equivalent single-layer storage formation is analysed. It was found that for the two cases the pore pressure evolution is similar, but the differences in the evolution of CO2 saturation are significant, which is attributed to the differences in CO2 spread in a single and three-layer storage. No fault reactivation was observed in either case. A sensitivity analysis was made to study the influence of the fault dip angle, the ratio between the horizontal and vertical stresses, the offset of the layers across fault F2, the initial permeability of the fault and the permeability of the confinement formations. Results show that reactivation of faults Fl and F2 is most sensitive to the stress ratio, the initial permeability of the faults and the permeability of the confinement formations. The offset of the layers across the fault F2 was also found to be an important parameter, mainly because an offset leads to an increase in CO2 leakage. Changes in permeability were found to be small because plastic shear strains induced by the reactivation of the faults and associated increase in volumetric strains and permeability, occur mainly in a fault section of only 10 m length, which is the approximate total thickness of the storage layers.

  • 28.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA..
    Rutqvist, Jonny
    Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A study of changes in deep fractured rock permeability due to coupled hydro-mechanical effects2015In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 79, p. 70-85Article in journal (Refereed)
    Abstract [en]

    This paper presents a numerical study of the hydro-mechanical behaviour of a fractured rock domain at 1000 m depth below the land surface as a function of different levels of fluid pore pressure. A 2D fractured rock domain is adopted based on data obtained from outcrop mapping, displaying multiple fracture sets, fracture intersections, dead-end and curved fractures. A continuum based numerical model is used to evaluate the effects of compressive boundary stresses, cracking by tension failure in the intact rock and fractures and shear displacement along fractures on its equivalent permeability. Two in situ stress boundary conditions are considered: an isotropic case SR1 with the two horizontal boundary compressive stresses having the same magnitude, and an anisotropic case SR2 with the ratio between these compressive stress components set to be 2. In the SR2 case, changes in the local stress and stress ratio distributions due to different fluid pore pressure levels are anisotropic and more significant than in the SR1 case, because of tension failures in the intact rock forming bridges between fractures. These failure regions opened new flow connections between fractures and thereby caused important anisotropic changes in the flow paths, and significant decrease in local gradients of fluid pore pressure. The equivalent permeability increases sharply when the fluid pore pressure is approximately 90% of the magnitude of the minimum stress at the boundaries of the fractured rock domain. Results show that the equivalent permeability of the fractured rock domain is most sensitive to the fractures normal stiffness, the permeability of the tension failure regions and the power-law exponent for permeability change.

  • 29.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley Natl Lab, Berkeley, CA USA.
    Rutqvist, Jonny
    Lawrence Berkeley Natl Lab, Berkeley, CA USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Corrigendum to “The effects of nearby fractures on hydraulically induced fracture propagation and permeability changes”[Eng. Geol. 228 (2017) 197–213]2018In: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917, Vol. 239, p. 344-344Article in journal (Other academic)
  • 30.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley National Laboratory, Berkeley, California.
    Rutqvist, Jonny
    Lawrence Berkeley National Laboratory.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Study of hydraulic fracturing processes in shale formations with complex geological settings2017In: Journal of Petroleum Science and Engineering, ISSN 0920-4105, E-ISSN 1873-4715, Vol. 152, p. 361-374Article in journal (Refereed)
    Abstract [en]

    Hydraulic fracturing has been applied to extract gas from shale-gas reservoirs. Complicated geological settings,such as spatial variability of the rock mass properties, local heterogeneities, complex in situ stress field, and preexistingbedding planes and faults, could make hydraulic fracturing a challenging task. In order to effectivelyand economically recover gas from such reservoirs, it is crucial to explore how hydraulic fracturing performs insuch complex geological settings. For this purpose, numerical modelling plays an important role because suchconditions cannot be reproduced by laboratory experiments. This paper focuses on the analysis of the influenceof confining formations and pre-existing bedding planes and faults on the hydraulically-induced propagation ofa vertical fracture, which will be called injection fracture, in a shale-gas reservoir. An elastic-brittle model basedon material property degradation was implemented in a 2D finite-difference scheme and used for rock elementssubjected to tension and shear failure. A base case is considered, in which the ratio SR between the magnitudesof the horizontal and vertical stresses, the permeability kc of the confining formations, the elastic modulus Epand initial permeability kp of the bedding plane and the initial fault permeability kF are fixed at reasonablevalues. In addition, the influence of multiple bedding planes, is investigated. Changes in pore pressure andpermeability due to high pressure injection lasting 2 h were analysed. Results show that in our case during theinjection period the fracture reaches the confining formations and if the permeability of those layers issignificantly larger than that of the shale, the pore pressure at the extended fracture tip decreases and fracturepropagation becomes slower. After shut-in, the pore pressure decreases more and the fracture does notpropagate any more. For bedding planes oriented perpendicular to the maximum principal stress direction andwith the same elastic properties as the shale formation, results were found not to be influenced by theirpresence. In such a scenario, the impact of multiple bedding planes on fracture propagation is negligible. On theother hand, a bedding plane softer than the surrounding shale formation leads to a fracture propagationasymmetrical vertically with respect to the centre of the injection fracture with a more limited upward fracturepropagation. A pre-existing fault leads to a decrease in fracture propagation because of fault reactivation withshear failure. This results in a smaller increase in injection fracture permeability and a slight higher injectionpressure than that observed without the fault. Overall, results of a sensitivity analysis show that fracturepropagation is influenced by the stress ratio SR, the permeability kc of the confining formations and the initialpermeability kp of the bedding plane more than the other major parameters.

    The full text will be freely available from 2019-03-07 08:00
  • 31.
    Figueiredo, Bruno
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lawrence Berkeley Natl Lab, Berkeley, CA USA.
    Rutqvist, Jonny
    Lawrence Berkeley Natl Lab, Berkeley, CA USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    The effects of nearby fractures on hydraulically induced fracture propagation and permeability changes2017In: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917, Vol. 228, p. 197-213Article in journal (Refereed)
    Abstract [en]

    Fracture propagation caused by hydraulic fracturing operations can be significantly influenced by adjacent fractures. This paper presents a detailed coupled hydro-mechanical analysis to study the effects of nearby natural fractures on hydraulically induced fracture propagation and changes in fracture permeability. Two rock domains were considered in comparison: FD1, with one fracture, and FD2, with two adjacent parallel or non-parallel fractures. It was assumed that water injection occurred in a borehole that intersected the single fracture in FD1 and one of the two fractures in FD2. Simulations were made for a time period of 3 h with an injection period of 2 h followed by 1 h of shut-in. An elastic-brittle model based on the degradation of material properties was implemented in a 2D finite-difference scheme and used for elements of the intact rock subjected to tension and shear failure. The intact rock was considered to have a low but non-negligible permeability. A verification study against analytical solutions showed that the fracture propagation and stress concentrations due to differential boundary stresses could be accurately represented by our model. Next, a base case was considered, in which the stress ratio (SR) between the magnitudes of the maximum and minimum boundary stresses, the permeability kR of the intact rock and the initial permeability kTF of the tension failure regions were fixed. In FD2, the distance dF between the two natural fractures defined by the closest distance was also fixed. The results showed that in both rock domains, the fracture started to propagate when the pore pressure was approximately 85% of the magnitude of the minimum boundary stress. The propagation of a single fracture was significantly greater than the propagation of a double fracture system because, in the latter case, the pore pressure decreased when the two fractures connected. As a result, changes in permeability in FD2 were smaller than in FD1. At the end of injection, the maximum ratios between the final and initial permeability of the natural fractures were found to be approximately 3 and 2 for rock domains FD1 and FD2, respectively. For non-parallel fractures, the controlling factor for fracture propagation was the separation between the tips of the pressurised fracture and the neighbouring non-pressurised fracture. A sensitivity study was conducted to study the influence of the key parameters dF, SR, kR and kTF on the simulation results. Fracture propagation showed more sensitivity to dF and SR than to the other parameters.

  • 32.
    Hedayati, Maryeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Wigston, Andrew
    Wolf, Jan Lennard
    Rebscher, Dorothee
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Impacts of SO2 gas impurity within a CO2 stream on reservoir rock of a CCS pilot site: Experimental and modelling approach2018In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 70, p. 32-44Article in journal (Refereed)
    Abstract [en]

    In order to evaluate chemical impacts of SO2 impurity on reservoir rock during CO2 capture and storage in deep saline aquifers, several batch reactor experiments were performed on laboratory scale using core rock samples from the pilot CO2 injection site in Heletz. In this experiment, the samples were exposed to pure N-2(g), pure CO2(g), and CO2(g) with an impurity of 1.5% SO2(g) under reservoir conditions for pressure and temperature (14.5 MPa, 60 degrees C). Based on the set-up and the obtained experimental results, a batch chemical model was established using the numerical simulation program TOUGHREACT V3.0-OMP. Comparing laboratory and simulation data provides a better understanding of the rock-brine-gas interactions. In addition, it offers an evaluation of the capability of the model to predict chemical interactions in the target injection reservoir during exposure to pure and impure CO2. The best match between the geochemical model and experimental data was achieved when the reactive surface area of minerals in the model was adjusted in order to calibrate the kinetic rates of minerals. The simulations indicated that SO2(g) tends to dissolve rather quickly and oxidizes under a kinetic control. Hence, it has a stronger effect on the acidity of the brine than pure CO2(g) and as a result, increased mineral dissolution and caused the precipitation of sulfate and sulfide minerals. Ankerite, dolomite, and siderite, the most abundant carbonates in the sandstone rock sample, are subject to stronger dissolution in the presence of SO2 gas. The performed simulations confirmed a slower dissolution rate for ankerite and siderite than for dolomite. The model reproduced the precipitation of pyrite and anhydrite as observed in the laboratory. The dissolution of dolomite observed in the batch reaction test with pure N-2 is assumed to be due to slight contamination with oxygen and modelling supported this. The inclusion of SO2 increased the porosity over that of the pure CO2 case, and is thus considered to increase the permeability and injectivity of the reservoir as well. Exposure to SO2 also increased the concentration of trace elements. The calibrated kinetic parameters determined in this study will be used to model the injection and long-term behavior of CO2 at the Heletz field site, and may be used for similar geologic reservoirs.

  • 33.
    Joodaki, Saba
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Juhlin, Christopher
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Sopher, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ivandic, Monika
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Erlström, Mikael
    SGU.
    Simulation of CO2 injection into a Baltic Sea saline aquifer and seismic monitoring of the plume2013In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, p. 355-364Article in journal (Refereed)
    Abstract [en]

    TOUGH2/ECO2N was used to simulate CO2 injection into a saline aquifer in the Baltic Sea and the effect of different amounts of CO2 injection on the seismic response. The Biot-Gassmann model was used to convert the simulated saturation and densities to seismic velocities and synthetic seismic responses before and after injection were compared. The results show that the amplitude changes in the seismic response are detectable even for small amounts of injected CO2, while noticeable signs of velocity pushdown, as a signature of the CO2 substitution, could only be observed if the injection rate is high enough.

  • 34.
    Joodaki, Saba
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    The effect of designing parameter of WAG injection on enhancement of CO2trapping in heterogeneous formations: A numerical study2017In: Greenhouse Gases: Science and Technology, E-ISSN 2152-3878, Vol. 7, no 6, p. 1008-1019Article in journal (Refereed)
    Abstract [en]

    Dissolution and residual trapping of CO2 injected in saline aquifers can be influenced by injection strategies applied. In this study, we focus on the water-alternating-gas (WAG) strategy and investigate the importance of parameters needed to design an effective WAG injection sequence, including (i) CO2 and water injection rates, (ii) WAG ratio, and (iii) number of cycles. Using TOUGH2-ECO2N, we perform 3D numerical simulations of sequences of CO2 and water injection into a heterogeneous formation. Hysteresis in relative permeability and capillary pressure functions is considered based on the Land trapping model. Results show that to design a WAG injection in a high permeable formation, the WAG ratio and number of injection cycles are more important parameters than the CO2 and water injection rates. Increasing the total amount of water injection (i.e., decreasing the WAG ratio for given total amount of injected CO2) improves the CO2 dissolution and residual trapping. It is also shown that increasing the number of injection cycles has a negative effect on both residual and dissolution trapping as measured at the end of the injection sequence, because both the free-phase and the dissolved CO2 plumes in the one-cycle injection scenario reach farther distances and occupy larger reservoir volumes than in the multi-cycle injection. This result means that while water injection following the CO2 injection improves trapping in comparison with the CO2-only injection strategy, the WAG scheme with multiple cycles should not be chosen to enhance trapping for the scenario considered in this study. 

  • 35. Kuehn, Michael
    et al.
    Busch, Andreas
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Amann-Hildenbrand, Alexandra
    Kempka, Thomas
    Lueth, Stefan
    CO2 storage is feasible and further demonstration projects are needed CO2 storage at the EGU general assembly 2012 Preface2013In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 19, p. 606-608Article in journal (Other academic)
  • 36. Kuusela-Lahtinen, Auli
    et al.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Luukkonen, Ari
    Flow Dimension as an Indicator of Hydraulic Behavior in Site Characterization of Fractured Rock2003In: Ground Water, ISSN 0017-467X, E-ISSN 1745-6584Article in journal (Refereed)
  • 37.
    Larsson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Doughty, Christine
    Lawrence Berkeley National Laboratory, CA, USA.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Understanding the effect of single fracture heterogeneity from single well injection withdrawal (SWIW) tests2013In: Hydrogeology Journal, ISSN 1431-2174, E-ISSN 1435-0157, Vol. 21, no 8, p. 1691-1700Article in journal (Refereed)
    Abstract [en]

    The single well injection withdrawal (SWIW) tracer test on a fracture or fracture zone is a method used to estimate its tracer retardation properties.  In this study, the effects of single fracture aperture heterogeneity on SWIW test tracer breakthrough curves are examined by numerical modelling. The effects of the matrix diffusion and sorption is accounted for by using a particle tracking method through the addition of a time delay added to the advective transport time. For a given diffusion and sorption property value (Pm) and for a heterogeneous fracture, the peak concentration is larger compared to a homogeneous fracture. The cumulative breakthrough curve for a heterogeneous fracture is similar to that for a homogeneous fracture and a less sorptive/diffusive tracer. It is demonstrated that the fracture area that meets the flowing water, the so-called specific flow-wetted surface (sFWS) of the fracture, can be determined by comparing the observed breakthrough curve for a heterogeneous fracture with that for a homogeneous fracture. SWIW tests are also simulated with a regional pressure gradient present. The results point to the possibility of distinguishing the effect of the regional pressure gradient from that of diffusion through the use of multiple tracers with different Pm-values. 

  • 38.
    Larsson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A study of flow-wetted surface area in a single fracture as a function of its hydraulic conductivity distribution2012In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 48, p. W01508-Article in journal (Refereed)
    Abstract [en]

    The contact area between flowing water and rock-the flow-wetted surface (FWS)-is a main factor controlling the rock-matrix diffusion and sorption of flowing solute in a rock fracture. Flow channeling, therefore, has a strong effect on the retardation of mass transport due to the resulting lower contact area. This work presents a systematic study of the dependency between fracture aperture statistics and FWS in strongly heterogeneous fractures. Particle tracking is used to determine the transversal width of the particle flow lines, FWS, and beta factor, where beta is a variable that has been proposed as controlling tracer retention. The conductivity distribution over the fracture is assumed to be lognormal with standard deviation (sigma(ln) (K)) ranging from 0.23 to 4.61, with correlation lengths from 2% to 18% of the width of the flow domain. Results show a clear dependency between the specific flow-wetted surface (sFWS), defined as FWS divided by the total fracture area, and the standard deviation of the logarithm of fracture conductivity. The behavior is independent of the correlation length for the range of correlation lengths tested. The results are presented in the form of type curves and an empirical equation that provide a simple way to determine the sFWS as a function of sigma(ln) (K). This information can then be used to adjust the results of large-scale fracture network simulations by taking into account the effect of single fracture heterogeneity, an effect that is in practice infeasible to directly take into account in large-scale fracture network simulations.

  • 39.
    Larsson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    An observed error in PMPATH particle tracking algorithm for MODFLOW in case of varying porosity and a proposed correction2012In: Computers & Geosciences, ISSN 0098-3004, E-ISSN 1873-7803, Vol. 45, p. 1-3Article in journal (Refereed)
    Abstract [en]

    MODFLOW (Harbaugh and McDonald, 1996) is a code widely used for groundwater modeling. It has been used for numerous projects and thousands of articles have been published with results of MODFLOW, since the code was first released in 1983. Numerous codes have been developed around MODFLOW, the pre- and post processing code Processing MODFLOW (Chiang, 2005) being one example. This code includes the advective particle tracking code PMPATH (Chiang, 2005), especially convenient and commonly used for stochastic groundwater modeling analyses as it includes an easy-to-use random field generator. The particle tracking code has been regularly used to simulate the advective transport of contaminants and tracers (e.g. Stauffer, 2005; Hefting et al., 2006; Dhiman and Keshari, 2006).

    A suspected error in the PMPATH code was found by us, when studying flow and particle transport in a strongly heterogeneous hydraulic conductivity fields with co-varying porosity. It emerged in the form of calculated particle flow paths converging into narrower and narrower channels. After many attempts to understand the results turned out to be unsuccessful, we decided to check into details of the code and discovered a significant but non-obvious error. This error is discussed in this paper and a procedure to obtain the correct flow paths and travel times is proposed. 

  • 40.
    Larsson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Comparison of transport persistence and dispersion length for strongly heterogeneous conductivity fields2008Conference paper (Other academic)
    Abstract [en]

    When modelling transport in fractured and other strongly heterogeneous media, the classical ADE-approach with a continuum dispersion coefficient is usually not applicable. This has led to the development of alternative approaches, often based on particle tracking. When upscaling travel time information by means of particle travel time distributions, it is, however, not obvious how the distributions of travel times among neighbouring elements should be spatially correlated. In our earlier works (Öhman et al, WRR 2005, WO3016, Oden at al. WRR 2008, WO2421) we have introduced the concept of transport persistence to account for this 'memory' of travel times. Transport persistence is a distance that, for example, a fast particle remains fast. The present study investigates the nature of transport persistence for different characteristics of the underlying hydraulic conductivity field – defined through the standard deviation and correlation length of K – and compares it to the classical dispersion length that can also be determined based on the statistical characteristics of the conductivity field. Flow and particle tracking simulations are carried out for heterogeneous conductivity fields for ten different combinations of standard deviation and correlation length values. Sixty realizations are considered for each combination, and for each realization a large number particles are released. The relationship between the transport persistence distance and the dispersion length is examined. Preliminary results indicate that the correlation between the two concepts depends on the values of the standard deviations of hydraulic conductivity, i.e., the degree of heterogeneity and transport channelling. Implications of these results will be discussed.

  • 41.
    Larsson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Odén, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Neretnieks, Ivars
    School of Chemical Science and Engineering, KTH, Stockholm.
    Tsang, Chin-Fu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A new approach to account for fracture aperture variability when modeling solute transport in fracture networks2013In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 49, no 4, p. 2241-2252Article in journal (Refereed)
    Abstract [en]

    A simple yet effective method is presented to include the effects of fracture aperture variability into the modeling of solute transport in fracture networks with matrix diffusion and linear sorption. Variable apertures cause different degrees of flow channeling, which in turn influence the contact area available for these retarding processes. Our approach is based on the concept of specific flow-wetted surface (sFWS), which is the fraction of the contact area over the total fracture surface area. Larsson et al. [2012] studied the relationship between sFWS and the standard deviation σln K  of the conductivity distribution over the fracture plane. Here an approach is presented to incorporate this into a fracture network model. With this model, solute transport through fracture networks is then analyzed. The cases of sFWS=0 and sFWS=1 correspond to those of no matrix diffusion and full matrix diffusion respectively. In between, a sFWS break point value can be defined, above which the median solute arrival time is proportional to the square of sFWS. For values below the critical sFWS (more channeled cases), the change is much slower, converging to that of no matrix diffusion. Results also indicate that details of assigning sFWS values for individual fractures in a network are not crucial; results of tracer transport are essentially identical to a case where all fractures have the mean σln K (or corresponding mean sFWS) value. This is obviously due to the averaging effect of the network.

  • 42. Mathew, M.
    et al.
    Illangasekare, T.H.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Sensitivity of model parameter in the prediction of DNAPL infiltration and redistribution in heterogeneous porous media2005In: Eos, Transaction, American Geophysical Union 86(52): Fall Meeting Supplement, Abstract H23A-1420, American Geophysical Union (AGU), 2005Conference paper (Refereed)
  • 43.
    Mathew, Mini
    et al.
    Colorado School of Mines.
    Illangesekare, Tissa
    Colardo School of Mines.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Parameter Sensitivity in the Prediction of DNAPL Infiltration and Redistribution in Heterogeneous Porous Media2006In: CMWR XVI - Computational Methods in Water Resources, 2006Conference paper (Refereed)
  • 44.
    Niemi, Auli
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bear, JacobTechnion-Israel Institute of Technology , Haifa, Israel.Bensabat, JacobTechnion-Israel Institute of Technology , Haifa, Israel.
    Geological Storage of CO2 in Deep Saline Formations: How to Tackle Search and Transfer Barriers2015Collection (editor) (Refereed)
    Abstract [en]

    This book describes the journey of developing and implementing a global knowledge sharing strategy at the multinational project development and construction company Skanska. The strategy described is based on a “people-to-people” approach and covers four different strategic business units with more than 50,000 employees. It shows how the introduction of knowledge management has led to improved collaboration on customers and increased sales, as well as quality improvements and higher employee satisfaction. The book introduces a 8-step framework for achieving sustainable organizational learning and provides a theoretical introduction to the field of knowledge management and cognitive pedagogy.

  • 45.
    Niemi, Auli
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Bensabat, Jacob
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sauter, Martin
    Ghergut, Julia
    Licha, Tobias
    Fierz, Thomas
    Wiegand, Gabriele
    Rasmusson, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Rasmusson, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Shtivelman, Vladimir
    Gendler, Michael
    Small-Scale CO2 Injection into a Deep Geological Formation at Heletz, Israel2012In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 23, p. 504-511Article in journal (Refereed)
    Abstract [en]

    This paper presents the experimental plans and designs as well as examples of predictive modeling of a pilot-scale CO2 injection experiment at the Heletz site (Israel). The overall objective of the experiment is to find optimal ways to characterize CO2 -relevant in-situ medium properties, including field-scale residual and dissolution trapping, to explore ways of characterizing heterogeneity through joint analysis of different types of data, and to detect leakage. The experiment will involve two wells, an injection well and a monitoring well. Prior to the actual CO2 injection, hydraulic, thermal and tracer tests will be carried out for standard site characterization. The actual CO2 injection experiments will include (i) a single well injection-withdrawal experiment, with the main objective to estimate in-situ residual trapping and (ii) a two-well injection-withdrawal test with injection of CO2 in a dipole mode (injection of CO2 in one well with simultaneous withdrawal of water in the monitoring well), with the objective to understand the CO2 transport in heterogeneous geology as well as the associated dissolution and residual trapping. Tracers will be introduced in both experiments to further aid in detecting the development of the phase composition during CO2 transport. Geophysical monitoring will also be implemented. By means of modeling, different experimental sequences and injection/withdrawal patterns have been analyzed, as have parameter uncertainties. The objectives have been to (i) evaluate key aspects of the experimental design, (ii) to identify key parameters affecting the fate of the CO2 and (iii) to evaluate the relationships between measurable quantities and parameters of interest.

  • 46.
    Niemi, Auli
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, Jacob
    Environm & Water Resources Engn EWRE Ltd, POB 6770, IL-31067 Haifa, Israel..
    Shtivelman, Vladimir
    Geophys Inst Israel, POB 182, IL-71100 Lod, Israel..
    Edlmann, Katriona
    Univ Edinburgh, Grant Inst, Sch Geosci, Kings Bldg,James Hutton Rd, Edinburgh EH9 3FE, Midlothian, Scotland..
    Gouze, Philippe
    Univ Montpellier, CNRS Geosci Montpellier, Campus Triolet CC060,Pl Eugene Batalluon, F-34095 Montpellier 05, France..
    Luquot, Linda
    Univ Montpellier, CNRS Geosci Montpellier, Campus Triolet CC060,Pl Eugene Batalluon, F-34095 Montpellier 05, France.;IDAEA, CSIC, Pascual Vila Bldg,Off 625 C Jordi Girona,18-26, Barcelona 08034, Spain..
    Hingerl, Ferdinand
    Stanford Univ, Global Climate & Energy Project, Jerry Yang & Akiko Yamazaki Environm & Energy Bld, Stanford, CA 94305 USA..
    Benson, Sally M.
    Stanford Univ, Global Climate & Energy Project, Jerry Yang & Akiko Yamazaki Environm & Energy Bld, Stanford, CA 94305 USA..
    Pezard, Philippe A.
    Univ Montpellier, CNRS Geosci Montpellier, Campus Triolet CC060,Pl Eugene Batalluon, F-34095 Montpellier 05, France..
    Rasmusson, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Uppsala Univ, Dept Earth Sci, Villavagen 16B, S-75236 Uppsala, Sweden..
    Tian, Liang
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Gendler, Michael
    Geophys Inst Israel, POB 182, IL-71100 Lod, Israel..
    Goldberg, Igor
    Geophys Inst Israel, POB 182, IL-71100 Lod, Israel..
    Tatomir, Alexandru
    Univ Gottingen, Angew Geol, Goldschmidtstr 3, D-37077 Gottingen, Germany..
    Lange, Torsten
    Univ Gottingen, Angew Geol, Goldschmidtstr 3, D-37077 Gottingen, Germany..
    Sauter, Martin
    Univ Gottingen, Angew Geol, Goldschmidtstr 3, D-37077 Gottingen, Germany..
    Freifeld, Barry
    Class VI Solut Inc, 711 Jean St, Oakland, CA 94610 USA..
    Heletz experimental site overview, characterization and data analysis for CO2 injection and geological storage2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 48, p. 3-23Article in journal (Refereed)
    Abstract [en]

    This paper provides an overview of the site characterization work at the Heletz site, in preparation to scientifically motivated CO2 injection experiments. The outcomes are geological and hydrogeological models with associated medium properties and baseline conditions. The work has consisted on first re-analyzing the existing data base from similar to 40 wells from the previous oil exploration studies, based on which a 3-dimensional structural model was constructed along with first estimates of the properties. The CO2 injection site is located on the saline edges of the Heletz depleted oil field. Two new deep (> 1600 m) wells were drilled within the injection site and from these wells a detailed characterization program was carried out, including coring, core analyses, fluid sampling, geophysical logging, seismic survey, in situ hydraulic testing and measurement of the baseline pressure and temperature. The results are presented and discussed in terms of characteristics of the reservoir and cap-rock, the mineralogy, water composition and other baseline conditions, porosity, permeability, capillary pressure and relative permeability. Special emphasis is given to petrophysical properties of the reservoir and the seal, such as comparing the estimates determined by different methods, looking at their geostatistical distributions as well as changes in them when exposed to CO2.

  • 47.
    Niemi, Auli
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Gouze, Philippe
    Univ Montpellier, CNRS, Geosci Montpellier, Montpellier, France..
    Bensabat, Jacob
    EWRE Ltd, Haifa, Israel..
    Characterization of formation properties for geological storage of CO2 - Experiences from the Heletz CO2 injection site and other example sites from the EU FP7 project MUSTANG Preface2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 48, p. 1-2Article in journal (Other academic)
  • 48.
    Porter, Richard T. J.
    et al.
    UCL, Dept Chem Engn, London WC1E 7JE, England.;Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Mahgerefteh, Haroun
    UCL, Dept Chem Engn, London WC1E 7JE, England..
    Brown, Solomon
    UCL, Dept Chem Engn, London WC1E 7JE, England.;Univ Sheffield, Dept Chem & Biol Engn, London S1 3JD, England..
    Martynov, Sergey
    UCL, Dept Chem Engn, London WC1E 7JE, England..
    Collard, Alexander
    UCL, Dept Chem Engn, London WC1E 7JE, England..
    Woolley, Robert M.
    Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Fairweather, Michael
    Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England..
    Falle, Samuel A. E. G.
    Univ Leeds, Sch Math, Leeds LS2 9JT, W Yorkshire, England..
    Wareing, Christopher J.
    Univ Leeds, Sch Phys & Astron, Leeds LS2 9JT, W Yorkshire, England..
    Nikolaidis, Ilias K.
    Natl Ctr Sci Res Demokritos, Inst Nanosci & Nanotechnol, Mol Thermodynam & Modelling Mat Lab, GR-15310 Aghia Paraskevi, Attikis, Greece..
    Boulougouris, Georgios C.
    Natl Ctr Sci Res Demokritos, Inst Nanosci & Nanotechnol, Mol Thermodynam & Modelling Mat Lab, GR-15310 Aghia Paraskevi, Attikis, Greece..
    Peristeras, Loukas D.
    Natl Ctr Sci Res Demokritos, Inst Nanosci & Nanotechnol, Mol Thermodynam & Modelling Mat Lab, GR-15310 Aghia Paraskevi, Attikis, Greece..
    Tsangaris, Dimitrios M.
    Natl Ctr Sci Res Demokritos, Inst Nanosci & Nanotechnol, Mol Thermodynam & Modelling Mat Lab, GR-15310 Aghia Paraskevi, Attikis, Greece..
    Economou, Ioannis G.
    Natl Ctr Sci Res Demokritos, Inst Nanosci & Nanotechnol, Mol Thermodynam & Modelling Mat Lab, GR-15310 Aghia Paraskevi, Attikis, Greece..
    Salvador, Carlos
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Zanganeh, Kourosh
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Wigston, Andrew
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Najafali, John N.
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Shafeen, Ahmed
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Beigzadeh, Ashkan
    Nat Resources Canada, CanmetENERGY, Ottawa, ON K1A 1M1, Canada..
    Farret, Regis
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Gombert, Phillipe
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Hebrard, Jerome
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Proust, Christophe
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Ceroni, Anthony
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Flauw, Yann
    INERIS, Parc Technol ALATA,Verneuil En Halatte BP 2, F-60550 Verneuil En Halatte, France..
    Zhang, Yongchun
    Dalian Univ Technol, Sch Chem Engn, Dalian, Peoples R China..
    Chen, Shaoyun
    Dalian Univ Technol, Sch Chem Engn, Dalian, Peoples R China..
    Yu, Jianliang
    Dalian Univ Technol, Sch Chem Engn, Dalian, Peoples R China..
    Talemi, Reza H.
    ArcelorMittal Global R&D Gent OCAS NV, Pres JF Kennedylaan 3, B-9060 Zelzate, Belgium..
    Bensabat, Jacob
    Environm & Water Resources Engn Ltd, Haifa, Israel..
    Wolf, Jan Lennard
    Bundesanstalt Geowissensch & Rohstoffe BGR, Geozentrum Hannover, Stilleweg 2, D-30655 Hannover, Germany..
    Rebscher, Dorothee
    Bundesanstalt Geowissensch & Rohstoffe BGR, Geozentrum Hannover, Stilleweg 2, D-30655 Hannover, Germany..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Jung, Byeongju
    UCL, Dept Chem Engn, London WC1E 7JE, England.;Korea Inst Geosci & Mineral Resources, Div Earth Environm Res, Daejeon 305350, South Korea..
    Mac Dowell, Niall
    Imperial Coll London, Ctr Environm Policy, London SW7 1NA, England.;Imperial Coll London, Dept Chem Engn, Ctr Proc Syst Engn, London SW7 2AZ, England..
    Shah, Nilay
    Imperial Coll London, Dept Chem Engn, Ctr Proc Syst Engn, London SW7 2AZ, England..
    Kolster, Clea
    Imperial Coll London, Dept Chem Engn, Ctr Proc Syst Engn, London SW7 2AZ, England..
    Mechleri, Evgenia
    Imperial Coll London, Dept Chem Engn, Ctr Proc Syst Engn, London SW7 2AZ, England..
    Krevor, Sam
    Imperial Coll London, Dept Chem Engn, Ctr Proc Syst Engn, London SW7 2AZ, England..
    Techno-economic assessment of CO2 quality effect on its storage and transport: CO(2)QUEST An overview of aims, objectives and main findings2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 54, p. 662-681Article in journal (Refereed)
    Abstract [en]

    This paper provides an overview of the aims, objectives and the main findings of the CO(2)QUEST FP7 collaborative project, funded by the European Commission and designed to address the fundamentally important and urgent issues regarding the impact of the typical impurities in CO2 streams captured from fossil fuel power plants and other CO2 intensive industries on their safe and economic pipeline transportation and storage. The main features and results recorded from some of the unique test facilities constructed as part of the project are presented. These include an extensively instrumented realistic-scale test pipeline for conducting pipeline rupture and dispersion tests in China, an injection test facility in France to study the mobility of trace metallic elements contained in a CO2 stream following injection near a shallow-water qualifier and fluid/rock interactions and well integrity experiments conducted using a fully instrumented deep-well CO2/impurities injection test facility in Israel. The above, along with the various unique mathematical models developed, provide the fundamentally important tools needed to define impurity tolerance levels, mixing protocols and control measures for pipeline networks and storage infrastructure, thus contributing to the development of relevant standards for the safe design and economic operation of CCS.

  • 49.
    Rasmusson, Kristina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Erlström, Mikael
    Sveriges geologiska undersökning (SGU).
    Subsurface characterisation and modeling of a CO2 test site in south Scania, Sweden, with special emphasis on the treatment of hydrogeological heterogeneity2011Conference paper (Refereed)
    Abstract [en]

    The south Scania site is one of the five test sites included in the MUSTANG project (EU FP7 programme) with an objective to understand - by means of experimental and simulation studies - the spreading and trapping of injected CO2 in different type saline formations. The geological setting of the site is an example of a typical multilayered sequence commonly found in sedimentary basins all over the world. It is analyzed here as an example of such sequence of primary and secondary traps and seal units. Particular emphasis is given for the characterization and quantification of the geological heterogeneity, in terms of what can be described in deterministic terms and where a stochastic representation is needed.

    For constructing the conceptual model, detailed hydrogeological and hydrogeochemical data is available in one deep well originally drilled for geothermal investigations, including an extensive hydrogeological testing programme. In addition, comprehensive data sets and analyses exist in 15 adjacent wells, allow definition of the characteristics of different lithological units and boundary layers with some confidence. The geology is dominated by a relatively thick (1200–1600 m) sequence of Upper Cretaceous strata, overlying a 400–600 m thick Lower Cretaceous, Jurassic and Triassic sequence of claystone and sandstone layers. Eight lithologic units have been mapped and characterised, the primary trap aquifer for this study being about 10 m thick sandstone and secondary traps having thicknesses between 10 and 50 metres, with lower overall permeabilities than the primary target. The primary seal consist of a several hundred meters thick limestone and the intermediate seals of claystone and mudstone. The lateral correlations of the layers between wells are based on lithological descriptions of cuttings, biostratigraphical analyses and geophysical well log correlation.

    One of the challenges for modeling the spreading of injected CO2 is to understand and to be able to quantify the characteristics of the horizontal heterogeneity and continuity of the layers between the boreholes. For this purpose, both a deterministic and a probabilistic/stochastic approach are used here to describe 1) the distribution of the depositional settings and 2) the properties (heterogeneity) within the units, in particular in terms of the distribution of the permeability values. Importance of the choice of the approach is discussed based on preliminary model simulations of CO2 injection using the various assumptions.

  • 50.
    Rasmusson, Kristina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Rasmusson, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bensabat, J.
    Tsang, Y.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Analysis of alternative push-pull-test-designs for determining in situ residual trapping of carbon dioxide2014In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 27, p. 155-168Article in journal (Refereed)
    Abstract [en]

    Carbon dioxide storage in deep saline aquifers is a promising technique to reduce direct emissions of greenhouse gas to the atmosphere. To ensure safe storage the in situ trapping mechanisms, residual trapping being one of them, need to be characterized. This study aims to compare three alternative single-well carbon dioxide push-pull test sequences for their ability to quantify residual gas trapping. The three tests are based on the proposed test sequence by Zhang et al. (2011) for estimating residual gas saturation. A new alternative way to create residual gas conditions in situ incorporating withdrawal and a novel indicator-tracer approach has been investigated. Further the value of additional pressure measurements from a nearby passive observation well was evaluated. The iTOUGH2 simulator with the EOS7C module was used for sensitivity analysis and parameter estimation. Results show that the indicator-tracer approach could be used to create residual conditions without increasing estimation uncertainty of S-gr. Additional pressure measurements from a passive observation well would reduce the uncertainty in the S-gr estimate. The findings of the study can be used to develop field experiments for site characterization.

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