Dynamics of basaltic glass dissolution - Capturing microscopic effects in continuum scale models

The method of ‘multiple interacting continua’ (MINC) was applied to include microscopic rate-limiting processes in continuum scale reactive transport models of basaltic glass dissolution. The MINC method involves dividing the system up to ambient fluid and grains, using a specific surface area to describe the interface between the two. The various grains and regions within grains can then be described by dividing them into continua separated by dividing surfaces. Millions of grains can thus be considered within the method without the need to explicity discretizing them. Four continua were used for describing a dissolving basaltic glass grain; the first one describes the ambient fluid around the grain, while the second, third and fourth continuum refer to a diffusive leached layer, the dissolving part of the grain and the inert part of the grain, respectively. The model was validated using the TOUGHREACT simulator and data from column flow through experiments of basaltic glass dissolution at low, neutral and high pH values. Successful reactive transport simulations of the experiments and overall adequate agreement between measured and simulated values provides validation that the MINC approach can be applied for incorporating microscopic effects in continuum scale basaltic glass dissolution models. Equivalent models can be used when simulating dissolution and alteration of other minerals. The study provides an example of how numerical modeling and experimental work can be combined to enhance understanding of mechanisms associated with basaltic glass dissolution. Column outlet concentrations indicated basaltic glass to dissolve stoichiometrically at pH 3. Predictive simulations with the developed MINC model indicated significant precipitation of secondary minerals within the column at neutral and high pH, explaining observed non-stoichiometric outlet concentrations at these pH levels. Clay, zeolite and hydroxide precipitation was predicted to be most abundant within the column.

[1]  T. J. Wolery,et al.  EQ3/6, a software package for geochemical modeling of aqueous systems: Package overview and installation guide (Version 7.0) , 1992 .

[2]  Y. Kharaka.  Reactive transport modeling to study changes in water chemistry induced by CO2 injection at the Frio-I brine pilot , 2010 .

[3]  S. Carroll,et al.  Amorphous silica precipitation (60 to 120°C): comparison of laboratory and field rates , 1998 .

[4]  S. Arnórsson,et al.  Redox reactions and potentials in natural waters at disequilibrium , 2005 .

[5]  J. Schott,et al.  Multisite surface reaction versus transport control during the hydrolysis of a complex oxide , 1988 .

[6]  Kevin G. Knauss,et al.  Reactive transport modeling of plug-flow reactor experiments: quartz and tuff dissolution at 240°C , 1998 .

[7]  K. Pruess,et al.  Modeling Multiphase Non-Isothermal Fluid Flow and Reactive Geochemical Transport in Variably Saturated Fractured Rocks: 2. Applications to Supergene Copper Enrichment and Hydrothermal Flows , 2001 .

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

[9]  T. Advocat,et al.  Kinetic aspects of basaltic glass dissolution at 90°C: role of aqueous silicon and aluminium , 1997 .

[10]  S. Gíslason,et al.  Regulation of arsenic mobility on basaltic glass surfaces by speciation and pH. , 2008, Environmental science & technology.

[11]  H. Jónsson,et al.  Development and evaluation of a thermodynamic dataset for phases of interest in CO2 mineral sequestration in basaltic rocks , 2012 .

[12]  W. Skinner,et al.  Early development of Al, Ca, and Na compositional gradients in labradorite leached in pH 2 HCl solutions , 2001 .

[13]  Luigi Marini,et al.  Geological Sequestration of Carbon Dioxide: Thermodynamics, Kinetics, and Reaction Path Modeling , 2006 .

[14]  S. Gíslason,et al.  Kinetic and thermodynamic properties of moganite, a novel silica polymorph , 1997 .

[15]  T. Advocat,et al.  Borosilicate Nuclear Waste Glass Alteration Kinetics: Chemical Inhibition and Affinity Control , 1997 .

[16]  Kathryn L. Nagy,et al.  Chemical weathering rate laws and global geochemical cycles , 1994 .

[17]  A. Paul.  Chemical durability of glasses; a thermodynamic approach , 1977 .

[18]  Hannes Jónsson,et al.  Multidimensional reactive transport modeling of CO2 mineral sequestration in basalts at the Hellisheidi geothermal field, Iceland , 2012 .

[19]  V. Daux,et al.  Dissolution rate of a basalt glass in silica-rich solutions: Implications for long-term alteration , 1994 .

[20]  Jean-Eric Lartigue,et al.  SON68 nuclear glass dissolution kinetics: Current state of knowledge and basis of the new GRAAL model , 2008 .

[21]  T. N. Narasimhan,et al.  A PRACTICAL METHOD FOR MODELING FLUID AND HEAT FLOW IN FRACTURED POROUS MEDIA , 1985 .

[22]  F. Poitrasson,et al.  Extreme iron isotope fractionation between colloids and particles of boreal and temperate organic-rich waters , 2013 .

[23]  J. D. Rimstidt,et al.  The kinetics of silica-water reactions , 1980 .

[24]  Karsten Pruess,et al.  TOUGHREACT Version 2.0: A simulator for subsurface reactive transport under non-isothermal multiphase flow conditions , 2011, Comput. Geosci..

[25]  T. Advocat,et al.  Dissolution kinetics of basaltic glasses: control by solution chemistry and protective effect of the alteration film , 2001 .

[26]  Karsten Pruess,et al.  Mineral Sequestration of Carbon Dixoide in a Sandstone-Shale System , 2004 .

[27]  Peter C. Lichtner,et al.  Continuum formulation of multicomponent-multiphase reactive transport , 1996 .

[28]  C. Steefel,et al.  A coupled model for transport of multiple chemical species and kinetic precipitation/dissolution rea , 1994 .

[29]  R. Millot,et al.  Experimental determination of the role of diffusion on Li isotope fractionation during basaltic glass weathering , 2011 .

[30]  Yousif K. Kharaka,et al.  A Compilation of Rate Parameters of Water-Mineral Interaction Kinetics for Application to Geochemical Modeling , 2004 .

[31]  L. Marini,et al.  The Double Solid Reactant Method for modeling the release of trace elements from dissolving solid phases: I. Outline and limitations , 2008 .

[32]  S. Gíslason,et al.  The mechanism, rates and consequences of basaltic glass dissolution: I. An experimental study of the dissolution rates of basaltic glass as a function of aqueous Al, Si and oxalic acid concentration at 25°C and pH = 3 and 11 , 2001 .

[33]  Carl I. Steefel,et al.  The mineral dissolution rate conundrum: Insights from reactive transport modeling of U isotopes and pore fluid chemistry in marine sediments , 2006 .

[34]  Thierry Advocat,et al.  Initial and long-term dissolution rates of aluminosilicate glasses enriched with Ti, Zr and Nd , 1999 .

[35]  Gudmundur S. Bodvarsson,et al.  A dual-porosity reservoir model with an improved coupling term , 1992 .

[36]  P. Frugier,et al.  Glass–water interphase reactivity with calcium rich solutions , 2011 .

[37]  K. Pruess,et al.  MODELING MULTIPHASE NON-ISOTHERMAL FLUID FLOW AND REACTIVE GEOCHEMICAL TRANSPORT IN VARIABLY SATURATED FRACTURED ROCKS: 1. METHODOLOGY , 2001 .

[38]  S. Gíslason,et al.  Mechanism, rates, and consequences of basaltic glass dissolution: II. An experimental study of the dissolution rates of basaltic glass as a function of pH and temperature , 2003 .

[39]  D. K. Smith,et al.  A Kinetic Model for Borosilicate Glass Dissolution Based on the Dissolution Affinity of a Surface Alteration Layer , 1989 .

[40]  S. Gíslason,et al.  CHEMICAL WEATHERING OF BASALTS, SOUTHWEST ICELAND: EFFECT OF ROCK CRYSTALLINITY AND SECONDARY MINERALS ON CHEMICAL FLUXES TO THE OCEAN , 2001 .

[41]  William L. Bourcier,et al.  Current status of the EQ3/ 6 software package for geochemical modeling , 1990 .

[42]  Karsten Pruess,et al.  TOUGHREACT - A simulation program for non-isothermal multiphase reactive geochemical transport in variably saturated geologic media: Applications to geothermal injectivity and CO2 geological sequestration , 2006, Comput. Geosci..

[43]  Karsten Pruess,et al.  TOUGHREACT User's Guide: A Simulation Program for Non-isothermal Multiphase Reactive geochemical Transport in Variable Saturated Geologic Media , 2004 .

[44]  Bernd Grambow,et al.  First-order dissolution rate law and the role of surface layers in glass performance assessment , 2001 .

[45]  B. Sigfússon.  Reactive transport of arsenic through basaltic porous media , 2009 .

[46]  S. Gíslason,et al.  The effect of fluoride on the dissolution rates of natural glasses at pH 4 and 25°C , 2004 .

[47]  Carl I. Steefel,et al.  Evaluation of the impact of CO2, co-contaminant gas, aqueous fluid and reservoir rock interactions on the geologic sequestration of CO2 , 2005 .

[48]  D. Langmuir.  Aqueous Environmental Geochemistry , 1997 .