Well injectivity during CO2 storage operations in deep saline aquifers – Part 2: Numerical simulations of drying, salt deposit mechanisms and role of capillary forces

The injection of CO2 into geological reservoirs or deep saline aquifers is being studied to control global warming by limiting greenhouse gas emissions. CO2 is captured from exhaust gases in power plants or industrial units and stored in underground geological reservoirs. Return on experience with CO2 injection in the oil industry clearly shows that injectivity problems can be encountered due to several mechanisms including mineral dissolution/precipitation and physical alteration due to the complete desaturation of the near-wellbore zone. This study describes numerical modelling that is able to reproduce the experimental results of drying of brine-saturated sandstone cores by gas injection in the laboratory. The evolution of water and gas saturation profiles and the precipitation of salt inside the samples are followed with injection time. Numerical results agree well with experimental observations highlighting the key role played by capillary forces during the desiccation process (see the companion paper; Peysson et al., 2013). A tentative extrapolation of experimental results from laboratory scale to the near-well field scale is proposed. This approach is of major importance because it makes it possible to determine the optimal CO2 injection flow rate according to both the intrinsic petrophysical properties of the porous medium and initial brine salinities.

[1]  M. Köhler,et al.  Halite Scale Formation in Gas-Producing Wells , 2003 .

[2]  Lincoln Paterson,et al.  Coupling of geochemical reactions and convective mixing in the long-term geological storage of carbon dioxide , 2007 .

[3]  Injection of supercritical CO2 in brine saturated sandstone: Pattern formation during salt precipitation , 2011 .

[4]  Karsten Pruess.  Formation dry-out from CO2 injection into saline aquifers: 2. Analytical model for salt precipitation: FORMATION DRY-OUT FROM CO2 INJECTION, 2 , 2009 .

[5]  L. André,et al.  Predicting the surface tension of aqueous 1:1 electrolyte solutions at high salinity , 2010 .

[6]  Y. Peysson,et al.  Permeability alteration induced by drying of brines in porous media , 2012 .

[7]  D. Sinton,et al.  Aquifer-on-a-chip: understanding pore-scale salt precipitation dynamics during CO2 sequestration. , 2013, Lab on a chip.

[8]  Y. Yortsos,et al.  Flow‐through drying of porous media , 2006 .

[9]  D. Broseta,et al.  CO2/water interfacial tensions under pressure and temperature conditions of CO2 geological storage , 2007 .

[10]  S. Bachu,et al.  Relative Permeability Characteristics for Supercritical CO2 Displacing Water in a Variety of Potential Sequestration Zones in the Western Canada Sedimentary Basin , 2005 .

[11]  W. Wagner,et al.  The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use , 2002 .

[12]  K. Pruess,et al.  Thermohydrological conditions and silica redistribution near high‐level nuclear wastes emplaced in saturated geological formations , 1988 .

[13]  Mohamed Azaroual,et al.  Numerical Simulations of the Thermal Impact of Supercritical CO2 Injection on Chemical Reactivity in a Carbonate Saline Reservoir , 2010 .

[14]  Y. Yortsos,et al.  Water removal from porous media by gas injection: experiments and simulation , 2007 .

[15]  W. Kleinitz,et al.  The Precipitation of Salt in Gas Producing Wells , 2001 .

[16]  K. Pruess,et al.  TOUGH2 User's Guide Version 2 , 1999 .

[17]  H. Bertin,et al.  Interfacial tension measurements and wettability evaluation for geological CO2 storage , 2009 .

[18]  Suzanne Hurter,et al.  Simulations for CO2 injection projects with Compositional Simulator , 2007 .

[19]  C. H. Whitson,et al.  Peng-Robinson predictions for hydrocarbons, CO2, N2, and H2 S with pure water and NaCI brine , 1992 .

[20]  Roland Okwen,et al.  NEAR-WELL PRESSURE DISTRIBUTION OF CO2 INJECTION IN A PARTIALLY PENETRATING WELL , 2012 .

[21]  Van Genuchten,et al.  A closed-form equation for predicting the hydraulic conductivity of unsaturated soils , 1980 .

[22]  Andreas Kopp,et al.  Monitoring of CO2 plumes during storage in geological formations using temperature signals: Numerical investigation , 2008 .

[23]  Philipp Blum,et al.  Chemical changes in fluid composition due to CO2 injection in the Altmark gas field: preliminary results from batch experiments , 2012, Environmental Earth Sciences.

[24]  C. Hofstee,et al.  Monitoring the CO2 injection site: K12-B , 2011 .

[25]  K. Pruess.  ECO2N: A TOUGH2 Fluid Property Module for Mixtures of Water, NaCl, and CO2 , 2005 .

[26]  S. Youssef,et al.  Permeability alteration due to salt precipitation driven by drying in the context of CO2 injection , 2011 .

[27]  Jeffrey A. Cunningham,et al.  Temporal variations in near-wellbore pressures during CO2 injection in saline aquifers , 2011 .

[28]  George J. Moridis,et al.  EOS7C Version 1.0: TOUGH2 Module for Carbon Dioxide or Nitrogen inNatural Gas (Methane) Reservoirs , 2004 .

[29]  Yildiray Cinar,et al.  Impact of Capillary Pressure, Salinity and In situ Conditions on CO2 Injection into Saline Aquifers , 2010 .

[30]  David William Keith,et al.  Analytical Solution to Evaluate Salt Precipitation during CO2 Injection in Saline Aquifers , 2009 .

[31]  L. André,et al.  Numerical modeling of fluid–rock chemical interactions at the supercritical CO2–liquid interface during CO2 injection into a carbonate reservoir, the Dogger aquifer (Paris Basin, France) , 2007 .

[32]  Alfredo Battistelli,et al.  2D modeling of salt precipitation during the injection of dry CO2 in a depleted gas reservoir , 2007 .

[33]  Karsten Pruess,et al.  Reactive transport modeling of injection well scaling and acidizing at Tiwi field, Philippines , 2004 .

[34]  K. Pruess,et al.  Two-dimensional reactive transport modeling of CO2 injection in a saline aquifer at the Sleipner site, North Sea , 2007, American Journal of Science.

[35]  T. Narasimhan,et al.  AN INTEGRATED FINITE DIFFERENCE METHOD FOR ANALYZING FLUID FLOW IN POROUS MEDIA , 1976 .

[36]  Karsten Pruess.  Numerical simulation of `multiphase tracer transport in fractured geothermal reservoirs , 2002 .

[37]  Mohamed Azaroual,et al.  Well injectivity during CO2 storage operations in deep saline aquifers—Part 1: Experimental investigation of drying effects, salt precipitation and capillary forces , 2014 .

[38]  I. Chou.  Phase relations in the system NaCl-KCl-H2O. III: Solubilities of halite in vapor-saturated liquids above 445°C and redetermination of phase equilibrium properties in the system NaCl-H2O to 1000°C and 1500 bars , 1987 .

[39]  Patrick Egermann,et al.  An Integrated Approach to Parameterize Reservoir Models for CO2 Injection in Aquifers , 2006 .

[40]  L. Appel,et al.  State of the science: promoting self-care in persons with heart failure: a scientific statement from the American Heart Association. , 2009, Circulation.