Modelling CO2 solubility in pure water and NaCl-type waters from 0 to 300 °C and from 1 to 300 bar: Application to the Utsira Formation at Sleipner

The goal of this study is to better quantify the solubility of CO2 in brines. New experimental data on the solubility of CO2 in a mixed salt solution at CO2 sequestration pressure and temperature conditions are presented. A thermodynamic model for calculation of the phase equilibria of CO2–H2O–NaCl system is briefly described; notably, the solubility of the carbon dioxide in the aqueous phase. This model was used to check his validity by comparing the calculation results with new experimental measurements, available experimental observations and other models CO2 solubility results. Comparison with experimental data indicates that the model can predict accurately CO2 solubility in pure water and in aqueous NaCl solutions of ionic strengths up to 3 molal from 1 to 300 °C and from 1 to 300 bar. This model has been applied to CO2 storage at Sleipner, North Sea. The salinity of the porewater within the Utsira Formation (the CO2 host formation) is approximately the same as seawater. Predicted CO2 solubility is in good agreement with new experimental measurements.

[1]  Stefan Bachu,et al.  Aquifer disposal of CO2: Hydrodynamic and mineral trapping , 1994 .

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

[3]  H. Helgeson,et al.  Theoretical prediction of the thermodynamic behavior of aqueous electrolytes by high pressures and temperatures; IV, Calculation of activity coefficients, osmotic coefficients, and apparent molal and standard and relative partial molal properties to 600 degrees C and 5kb , 1981 .

[4]  S. Bachu,et al.  Sequestration of CO2 in geological media in response to climate change: capacity of deep saline aquifers to sequester CO2 in solution , 2003 .

[5]  Zhijing Wang,et al.  Seismic properties of pore fluids , 1992 .

[6]  D. Peng,et al.  A New Two-Constant Equation of State , 1976 .

[7]  R. D. Deshmukh,et al.  Phase Equilibria in Aqueous Electrolyte Solutions , 1980 .

[8]  S. Takenouchi,et al.  The binary system H 2 O-CO 2 at high temperatures and pressures , 1964 .

[9]  Raymond E. Davis,et al.  The Ionization Constant of Carbonic Acid in Water and the Solubility of Carbon Dioxide in Water and Aqueous Salt Solutions from 0 to 50 , 1943 .

[10]  Zhenhao Duan,et al.  An improved model calculating CO2 solubility in pure water and aqueous NaCl solutions from 273 to 533 K and from 0 to 2000 bar , 2003 .

[11]  Jean-Charles de Hemptinne,et al.  Solubility of light hydrocarbons and their mixtures in pure water under high pressure , 1998 .

[12]  John H. Weare,et al.  An equation of state for the CH4-CO2-H2O system: I. Pure systems from 0 to 1000°C and 0 to 8000 bar , 1992 .

[13]  Shigeharu Kito,et al.  SALTING-OUT PARAMETERS OF GAS SOLUBILITY IN AQUEOUS SALT SOLUTIONS , 1970 .

[14]  J. P. Riley,et al.  The solubility of gases in distilled water and sea water—IV. Carbon dioxide , 1971 .

[15]  R. L. Savage,et al.  The Solubility of Carbon Dioxide in Calcium Chloride-Water Solutions at 75, 100, 120° and High Pressures1 , 1945 .

[16]  Ho Teng,et al.  Solubility of Liquid CO2 in Synthetic Sea Water at Temperatures from 278 K to 293 K and Pressures from 6.44 MPa to 29.49 MPa, and Densities of the Corresponding Aqueous Solutions , 1998 .

[17]  B. Rumpf,et al.  Solubility of carbon dioxide in aqueous solutions of sodium chloride: Experimental results and correlation , 1994 .

[18]  Ragnhild Korbol,et al.  Sleipner Vest CO2 Disposal, CO2 Injection Into A Shallow Underground Aquifer , 1996 .

[19]  R. Wiebe,et al.  The Solubility in Water of Carbon Dioxide at 50, 75 and 100°, at Pressures to 700 Atmospheres , 1939 .

[20]  R. Wiebe,et al.  The Solubility of Carbon Dioxide in Water at Various Temperatures from 12 to 40° and at Pressures to 500 Atmospheres. Critical Phenomena* , 1940 .

[21]  Fumitake Yoshida,et al.  Solubility of carbon dioxide in aqueous electrolyte solutions , 1979 .

[22]  C. Eckert,et al.  Generalized reference fugacities for phase equilibrium thermodynamics , 1965 .

[23]  H. Teng,et al.  Solubility of liquid CO2in water at temperatures from 278 K to 293 K and pressures from 6.44 MPa to 29.49 MPa and densities of the corresponding aqueous solutions , 1997 .

[24]  Andrew J. Weaver.  The Science of Climate Change , 2003 .

[25]  Nicolas Kalogerakis,et al.  Solubilities of carbon dioxide in water and 1 wt. % sodium chloride solution at pressures up to 10 MPa and temperatures from 80 to 200.degree.C , 1989 .

[26]  Wolfgang Wagner,et al.  International Equations for the Saturation Properties of Ordinary Water Substance , 1987 .

[27]  G. Maurer,et al.  Das Dampf-Flüssigkeitsgleichgewicht des ternären Systems Ammoniak-Kohlendioxid-Wasser bei hohen Wassergehalten im Bereich zwischen 373 und 473 Kelvin , 1988 .

[28]  J. S. Rowlinson,et al.  Molecular Thermodynamics of Fluid-Phase Equilibria , 1969 .

[29]  Karsten Pruess,et al.  Multiphase flow dynamics during CO2 disposal into saline aquifers , 2002 .

[30]  A. J. Ellis,et al.  The solubility of carbon dioxide above 100 degrees C in water and in sodium chloride solutions , 1963 .

[31]  D. Peng,et al.  Two- and Three-Phase Equilibrium Calculations for Coal Gasification and Related Processes , 1980 .

[32]  B. Rumpf,et al.  An Experimental and Theoretical Investigation on the Solubility of Carbon Dioxide in Aqueous Solutions of Strong Electrolytes , 1993 .

[33]  S. Takenouchi,et al.  The solubility of carbon dioxide in nacl solutions at high temperatures and pressures , 1965 .

[34]  K. Kobe,et al.  The Solubility of Carbon Dioxide and Nitrous Oxide in Aqueous Salt Solutions , 1941 .

[35]  K. Tödheide,et al.  Das Zweiphasengebiet und die kritische Kurve im System Kohlendioxid–Wasser bis zu Drucken von 3500 bar , 1963 .

[36]  J. P. Riley,et al.  The solubility of gases in distilled water and sea water—II. Oxygen , 1969 .

[37]  H. Helgeson,et al.  Thermodynamics of hydrothermal systems at elevated temperatures and pressures , 1969 .

[38]  Kenneth S. Pitzer,et al.  Thermodynamics of electrolytes. I. Theoretical basis and general equations , 1973 .

[39]  A. D. King,et al.  Solubility of water in compressed carbon dioxide, nitrous oxide, and ethane. Evidence for hydration of carbon dioxide and nitrous oxide in the gas phase , 1971 .