CCS and Power Systems

Carbon Storage - Geologic Storage Technologies and Simulation and Risk Assessment


Simulation of Coupled Processes of Flow, Transport and Storage of CO2 in Saline Aquifers


Performer: Colorado School of Mines

Project No: FE0000988


Accomplishments


  • A rock mechanics module for the reservoir model was
    modified. The modification includes an expression for how 
    variations in porosity and bulk volume depend on pressure 
    and effective stress. 
  • A model was set up to study the dissolution of calcite due to
    CO2
     injection in a one dimensional radial saline formation. 
    After 40 years of injection, the porosity change due to 
    dissolution was found to be less than 0.1% of the original 
    porosity (30%).
  • Model simulations have been conducted to study
    hydromechanical changes during CO2
     injection into a 
    hypothetical aquifer. The model was modified to include 
    thermoporoplastic effects
  • Geochemical reaction modeling is being carried out for the
    Colorado Plateau, Southern Rocky Mountain, and Gulf Coast 
    sediments. These are formations that have significant CO2
     storage potential.
  • A new fully coupled software modification was created
    to model reservoir flow and rock deformation, and 
    enhancements and improvements were made to the reservoir 
    model to account for mixtures of brine and CO2
    , three-phase 
    conditions of gaseous/ liquid CO2
     and water and super- and 
    sub-critical CO2
  • A new coupled calculation procedure and related algorithm
    were developed to address the fluid flow, solute transport, 
    and geochemical reaction portions of the model. The updated 
    mathematical equations and solution method were used 
    to solve the fluid flow, solute transport, and geochemical 
    reaction in a simplified isothermal geochemical reaction 
    system. This is the basic principle used to develop the new 
    reactive transport modeling code.
  • Simulations of convective mixing with density contrast caused
    by variable dissolved CO2
     concentration in saline water have 
    been initiated. Additionally, simulations of the In Salah Gas 
    Project were run on a computer cluster to demonstrate the 
    parallel code’s ability to simulate larger problems.
  • A batch reaction system was used to simulate the reactive
    geochemistry of CO2
     storage, which includes saline water, CO2
     
    gas and calcite. Geochemical reactions are fully accounted for 
    and all the chemical reactions involved in this batch reaction 
    system are set to be at equilibrium. The batch reaction model 
    was validated and compared to a commonly used simulator
  • A geochemical reaction module for the reservoir simulator
    has been developed. This module contains key reactions 
    identified during studies but has been made sufficiently 
    general to allow future extension so that the module can be 
    easily adapted to another saline aquifer with a different set 
    of dominant geochemical reactions.



Project Details