Predicting possible effects of H2S impurity on CO2 transportation and geological storage.

For CO(2) geological storage, permitting impurities, such as H(2)S, in CO(2) streams can lead to a great potential for capital and energy savings for CO(2) capture and separation, but it also increases costs and risk management for transportation and storage. To evaluate the cost-benefits, using a recently developed model (Ji, X.; Zhu, C. Geochim. Cosmochim. Acta 2012, 91, 40-59), this study predicts phase equilibria and thermodynamic properties of the system H(2)S-CO(2)-H(2)O-NaCl under transportation and storage conditions and discusses potential effects of H(2)S on transportation and storage. The prediction shows that inclusion of H(2)S in CO(2) streams may lead to two-phase flow. For H(2)S-CO(2) mixtures, at a given temperature, the bubble and dew pressures decrease with increasing H(2)S content, while the mass density increases at low pressures and decreases at high pressures. For the CO(2)-H(2)S-H(2)O system, the total gas solubility increases while the mass density of the aqueous solution with dissolved gas decreases. For the CO(2)-H(2)S-H(2)O-NaCl system, at a given temperature, pressure and NaCl concentration, the solubility of the gas mixture in aqueous phase increases with increasing H(2)S content and then decreases, while the mass density of aqueous solution decreases and may be lower than the mass density of the solution without gas dissolution.

[1]  Xiaoyan Ji,et al.  Ion-based SAFT2 to represent aqueous multiple-salt solutions at ambient and elevated temperatures and pressures , 2008 .

[2]  Victor Vilarrasa,et al.  Effects of CO2 Compressibility on CO2 Storage in Deep Saline Aquifers , 2010 .

[3]  Weon Shik Han,et al.  Effects of density and mutual solubility of a CO2-brine system on CO2 storage in geological formations: "Warm" vs. "cold" formations , 2009 .

[4]  Hendricks Franssen Harrie‐Jan,et al.  1 Thermodynamic model of aqueous CO 2 – H 2 O – NaCl solutions from − 22 to 100 ° C and from 0 . 1 to 100 MPa , 2010 .

[5]  Clare McCabe,et al.  Modeling the phase behavior, excess enthalpies and Henry's constants of the H2O + H2S binary mixture using the SAFT-VR+D approach , 2010 .

[6]  H. Tchelepi,et al.  Onset of convection in a gravitationally unstable diffusive boundary layer in porous media , 2005, Journal of Fluid Mechanics.

[7]  Xiaoyan Ji,et al.  SAFT1-RPM Approximation Extended to Phase Equilibria and Densities of CO2−H2O and CO2−H2O−NaCl Systems , 2005 .

[8]  Ioannis N. Tsimpanogiannis,et al.  Thermodynamic modeling of the vapor–liquid equilibrium of the CO2/H2O mixture , 2009 .

[9]  Xiaoyan Ji,et al.  A SAFT equation of state for the quaternary H2S–CO2–H2O–NaCl system , 2011 .

[10]  Hans Joachim Krautz,et al.  Modelling of the CO2 process- and transport chain in CCS systems—Examination of transport and storage processes , 2010 .

[11]  Theresa L. Watson,et al.  Review of failures for wells used for CO2 and acid gas injection in Alberta, Canada , 2009 .

[12]  Abbas Firoozabadi,et al.  Cubic‐plus‐association equation of state for water‐containing mixtures: Is “cross association” necessary? , 2009 .

[13]  Jesús Carrera,et al.  Effect of dispersion on the onset of convection during CO2 sequestration , 2009, Journal of Fluid Mechanics.

[14]  Sugata P. Tan,et al.  Statistical Associating Fluid Theory Coupled with Restricted Primitive Model To Represent Aqueous Strong Electrolytes , 2005 .

[15]  J. Gross,et al.  Modeling the phase equilibria of hydrogen sulfide and carbon dioxide in mixture with hydrocarbons and water using the PCP-SAFT equation of state , 2010 .

[16]  Zhenhao Duan,et al.  Accurate Thermodynamic Model for the Calculation of H2S Solubility in Pure Water and Brines , 2007 .

[17]  M. Blunt,et al.  A fast method to equilibrate carbon dioxide with brine at high pressure and elevated temperature including solubility measurements , 2012 .

[18]  Sugata P. Tan,et al.  Statistical associating fluid theory coupled with restrictive primitive model extended to bivalent ions. SAFT2: 1. Single salt + water solutions. , 2006, Journal of Physical Chemistry B.

[19]  Ir. Radboud Bisschop.  Tailor-made conceptual design of CO2 transport & injection facilities for the Barendrecht CO2 storage project; minimizing risk and optimizing lifecycle value , 2011 .

[20]  Marica Marcolini,et al.  TMGAS: A new TOUGH2 EOS module for the numerical simulation of gas mixtures injection in geological structures , 2009 .

[21]  Sugata P. Tan,et al.  Statistical associating fluid theory coupled with restrictive primitive model extended to bivalent ions. SAFT2: 2. Brine/seawater properties predicted. , 2006, The journal of physical chemistry. B.

[22]  J. Dubessy,et al.  Equation of state taking into account dipolar interactions and association by hydrogen bonding: II—Modelling liquid–vapour equilibria in the H2O–H2S, H2O–CH4 AND H2O–CO2 systems , 2008 .

[23]  Mohsen Zirrahi,et al.  Prediction of water content of sour and acid gases , 2010 .

[24]  Shengli Huang,et al.  Measurement and modeling of CO2 solubility in NaCl brine and CO2–saturated NaCl brine density , 2011 .

[25]  Yongan Gu,et al.  Accelerated mass transfer of CO2 in reservoir brine due to density-driven natural convection at high pressures and elevated temperatures , 2006 .

[26]  Jiafei Zhao,et al.  Density of Carbon Dioxide + Brine Solution from Tianjin Reservoir under Sequestration Conditions , 2011 .

[27]  Karsten Pruess,et al.  CO2-H2O mixtures in the geological sequestration of CO2. I. Assessment and calculation of mutual solubilities from 12 to 100°C and up to 600 bar , 2003 .

[28]  S. Bachu,et al.  Equations of state for basin geofluids: algorithm review and intercomparison for brines , 2002 .

[29]  L. Diamond,et al.  Thermodynamic model of aqueous CO2–H2O–NaCl solutions from -22 to 100 °C and from 0.1 to 100 MPa , 2010 .

[30]  N. Hilal,et al.  A simple model for the prediction of CO2 solubility in H2O–NaCl system at geological sequestration conditions , 2010 .

[31]  Xin Feng,et al.  Progress in the Study on the Phase Equilibria of the CO2-H2O and CO2-H2O-NaCl Systems * , 2007 .