Geochemistry 

Reactive Transport

Simulated flow and pH inside a crushed calcite capillary experiment (Molins et al., 2014 Environ. Sci. Technol.)
Simulated flow and pH inside a crushed calcite capillary experiment (Molins et al., Environ. Sci. Technol., 2014)

Berkeley Lab’s world-renowned expertise in reactive transport draws from a combined 100 years of experience in the field by scientists in the Geochemistry and Hydrogeology Departments. Close collaboration with the Computational Research Division (CRD) has built upon this expertise to bring in high performance computational tools. The group has played an integral role in developing two of the world’s most widely used reactive transport codes, TOUGHREACT and CrunchFlow. These capabilities are applied in-house to a range of important earth and environmental problems—

  • Contaminant fate and transport
  • Chemical weathering and geochemical kinetics
  • Geothermal processes
  • Biogeochemical cycling
  • Used fuel disposition in clay-bearing rocks
  • Waste form corrosion
  • CO2 injection and sequestration
Spatial distributions of pH in a CO<sub>2</sub> controlled-release field test CO<sub>2</sub> on a shallow groundwater system simulated with TOUGHREACT. (Zheng et al., Chemical Geology 2016)

Spatial distributions of pH in a CO2 controlled-release field test on a shallow groundwater system simulated with TOUGHREACT (From Zheng et al., Chemical Geology 2016.)

Building on the existing capabilities and on-going collaborations, the group continues to develop conceptual and numerical models to address a number of emerging topics—

  • Pore-scale reactive transport modeling
  • Coupling reactive transport to mechanical processes
  • Incorporation of isotopic systematic into multicomponent reaction networks
  • Development of coupled microbiological metabolic and biogeochemical models
  • Watershed-scale biogeochemical cycling
  • Osmotic transport of water in concentrated solutions
  • Explicit modeling of diffuse double layers and other electrochemical phenomena
(Left) Simulation of out-diffusion in the DR-A test conducted in Opalinus Clay at the Mont Terri site in Switzerland using CrunchFlow. (Right) Pseudo-2- D Cartesian system with diffusion along the x-axis and electrostatic potential developing along the y-axis due to the negative charge at clay mineral surfaces (Tounassat and Steefel, RiMG, 2015).

(Left) Simulation of out-diffusion in the DR-A test conducted in Opalinus Clay at the Mont Terri site in Switzerland using CrunchFlow. (Right) Pseudo-2- D Cartesian system with diffusion along the x-axis and electrostatic potential developing along the y-axis due to the negative charge at clay mineral surfaces (Tournassat and Steefel, RiMG, 2015).

Reactive Transport Software

Most software packages developed by the Reactive Transport group are available for research for free or at low academic pricing via open-source or academic licenses. Follow the links below for more information.

  • TOUGHREACT: numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media, developed by introducing reactive chemistry into the multiphase flow code TOUGH2. Developers: Nic Spycher, Eric Sonnenthal, Liange Zheng.
  • TOUGHREACT V3.0-OMP: major new release of TOUGHREACT that includes many new features and parallelization of the most CPU-intensive calculations in reactive-transport model simulations. Developer: Eric Sonnenthal
  • TOUGHREACT-Pitzer: reactive geochemical transport modeling of concentrated aqueous solutions based on the Pitzer ion-interaction model. Developer: Nic Spycher
  • CrunchFlow (Bitbucket): software package for multicomponent reactive flow and transport that can be used for simulation of a range of important processes and environments, including reactive contaminant transport, chemical weathering, carbon sequestration, biogeochemical cycling, and water-rock interaction. Principal developer: Carl Steefel
  • Chombo-Crunch: pore scale reactive transport code developed in collaboration with the Computational Research Division (CRD) based on the embedded-boundary adaptive mesh refinement software pacakage Chombo and the geochemical routines of CrunchFlow. Developers: David Trebotich (CRD), Sergi Molins.
  • Alquimia (Github): open-source software library that provides a generic interface to existing biogeochemical capabilities (currently, PFlotran and CrunchFlow) to facilitate interoperable code development. Github repo admin: Sergi Molins.
Flow chart for a multicomponent reactive flow and transport simulator

Flow chart for a multicomponent reactive flow and transport simulator