Shell International Exploration and Production

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Shell International Exploration and Production
Research and Technology

Passive Tracers in MoReS
Prepared for the FORCE seminar

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Improved description of gas mixing

• Objective
• develop reservoir simulation models to describe
  gas-gas mixing
• predict quality of produced gas under UGS
  conditions
• Mixing at different length scales
• microscopic (core, flow path tortuosity,
  molecular diffusion)
• macroscopic (geological unit, permeability
  heterogeneity)
• megascopic (layer-induced mixing)
• Computational effort
• up-scaling to field model (coupling of different
  length scales)
• reduction of numerical dispersion

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Grijpskerk UGS background
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Gas Mixing Mechanisms
Pore Level
Reservoir scale
Within Sand Interval
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Numerical dispersion
Indigeneous gas
Timestep
Injected gas
1 2 3

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Tracer distribution around GRK-11High-Res MoReS
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Tracer distribution around GRK-11 (high perm.
layer)Standard MoReS
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Tracer distribution around GRK-11 (low perm.
layer)Standard MoReS
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Separate (explicit) tracer solver
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Tracer distribution around GRK-11 (high perm.
layer)High-Res MoReS
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Tracer distribution around GRK-11 (low perm.
layer)High-Res MoReS
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Tracer distribution around GRK-11 (high perm.
layer)
Hi-Res MoReS
Conventional MoReS
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Single Well Tracer Test - Match (1)

• Excellent match early response
• tail mis-match due to ignoring dispersion within
  grid blocks

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Single Well Tracer Test - Match (2)

• Excellent match early response
• Improved match tail by re-introducing a physical
  diffusion and dispersion model

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Phase 2 Tracer Test - Design

• Gas Displacement

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Phase 2 Tracer Test - Preliminary results