Reactive transport of CO2 in a brine cavity

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Reactive transport of CO2 in a brine cavity

• Dirk and Meredith
• EGEE 520 Project Presentation

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Introduction

• CO2 emissions are increasing as a result of the
  combustion of fossil fuels
• Sequestering CO2 into deep saline aquifers is a
  viable method to reduce these emissions
• Geographic abundance
• Close proximity to industrial emission sources
• Favorable chemical compositions of saline waters
• Presence of Ca2, Mg2, Fe2, Sr2
• Sequestration mechanisms
• Hydrodynamic trapping CO2 exists as both
  immiscible and dissolved phases due to low flow
  velocity
• Mineral trapping Conversion of gaseous CO2 into
  solid carbonates

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Formulation

• Modeled system as 2-D system with sides of 1
  meter
• Process of modeling in steps
• Diffusion into a box
• Adding Navier-Stokes and advection diffusion with
  functions to describe the change in fluid density
  due to infusion of CO2.
• Adding a second advection diffusion equation for
  brine and the advection conduction equation for
  heat transfer
• Generate sinks with reaction and add the
  appropriate terms to advection diffusion and
  conduction equations

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Governing Equations
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Solution
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Verification
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Parametric Study
Temp Profile D0.001 tc500
CO2 Profile D0.001 tc100000
Temp Profile D0.001 tc5000
Original Solution CO2 Profile D0.00005 tc
100000
Original solution Temp Profile D0.00005
tc100000
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Conclusion

• CO2 emissions are going to remain an issue for
  years to come
• Research has shown that saline aquifers are
  viable for sequestering CO2
• The Navier-Stokes advective-diffusion and
  advective-conduction equations are known to model
  real behavior and have been verified with COMSOL
  3.2 in this study
• COMSOL 3.2 produces results that are reasonable
• Mass diffusion rate and thermal conductivity
  parameters play a major role in fluid behavior
• Given more resources, we are confident that an
  accurate model for this system could be attained