in the name of god pore-scale modeling of three-phase flow in mixed-wet systems mohammad piri martin...
TRANSCRIPT
In the name of God
Pore-Scale Modeling of Three-Phase Flow in Mixed-Wet Systems
Mohammad PiriMohammad Piri
Martin BluntMartin Blunt
Centre for Petroleum Studies
Department of Earth Science and Engineering
Imperial College, London
Outline
Why pore-scale modeling of three-phase flow?Why pore-scale modeling of three-phase flow?
Pore-scale configurations Pore-scale configurations
How we model displacement How we model displacement
Comparison with experimental data:Comparison with experimental data:
Two-phase water-wetTwo-phase water-wet
Three-phase water-wetThree-phase water-wet
Prediction of three-phase mixed-wet behaviorPrediction of three-phase mixed-wet behavior
Why three-phase flow?
Gas injectionGas injection
Depressurisation below the bubble pointDepressurisation below the bubble point
Solution gas driveSolution gas drive
Gravity drainageGravity drainage
Three-phase flow in the following situations:
Characterized by low oil saturations and huge uncertainty in relative permeability – experiments are difficult and empirical models are uncertain.
Network we use A realization of Berea sandstone (Statoil)A realization of Berea sandstone (Statoil)
UNSW, Australia
12,349 pores and 26,146 throats with square, circular or triangular cross-section.
The network has a disordered topology – can The network has a disordered topology – can be based on direct analysis of real pore spaces.be based on direct analysis of real pore spaces.
State-of the art physics: wettability State-of the art physics: wettability alteration, flow in corners and layers.alteration, flow in corners and layers.
Track saturation paths for any type of three-Track saturation paths for any type of three-phase displacement and predict relative phase displacement and predict relative permeability and capillary pressure.permeability and capillary pressure.
Potential use as a predictive tool or to Potential use as a predictive tool or to construct/validate empirical three-phase construct/validate empirical three-phase models.models.
Could be coupled to larger-scale simulation Could be coupled to larger-scale simulation directly.directly.
Our pore network model
Configuration E Configuration F Configuration G Configuration H
Configuration C Configuration DConfiguration A Configuration B
Two and three-phase configurations
GasWaterOil
Configuration J Configuration KConfiguration I Configuration L
Configuration NConfiguration M Configuration OConfiguration P
Two and three-phase configurations (Cont.)
GasWaterOil
Example displacement sequence
Configuration CConfiguration A Configuration B
Configuration EConfiguration G
Primary Drainage
Water Flooding
Gas Injection
Configuration I
Layer Collapsing
gw
go Gas Injection
GasWaterOil
How to simulate displacement
1. A displacement is a change from one configuration to another.
2. A capillary pressure for every possible displacement is calculated.
3. We assume quasi-static displacement.
4. We choose a displacement (what phase displaces what) and perform the displacement that occurs at the lowest invading phase pressure.5. Check for trapping.
6. Repeat the process, while tracking a specified saturation path.
Primary drainage prediction
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1
W ate r Saturation
Rel
ativ
e P
erm
eabi
lity
Two-phase primary drainage – water-wetExperimental data from Oak – SPE 20183
ExperimentPrediction
Waterflood prediction
Two-phase waterflooding – water-wetOil/water contact angle from 30o – 80o
Data from Oak – SPE 20183
0.0001
0.001
0.01
0.1
1
0 0.2 0.4 0.6 0.8 1
W ate r Saturation
Rel
ativ
e P
erm
eabi
lity
Three-Phase Saturation Paths
Three-phase steady state experiments – water-wetOil/water contact angle from 30o – 80o. Track saturations.Data from Oak – SPE 20183
SwSo
Sg
Three-phase oil relative permeabilities
Measured and predicted oil relative permeabilities for four experiments – gas into oil and water.
0.001
0.01
0.1
1
0 0.2 0.4 0.6 0.8 1
Oil Saturation
Oil
Re
lati
ve
Pe
rme
ab
ility
Experiment 8 (Measurements)
Experiment 8 (Predictions)
Experiment 9 (Measurements)
Experiment 9 (Predictions)
Experiment 10 (Measurements)
Experiment 10 (Predictions)
Experiment 20 (Measurements)
Experiment 20 (Predictions)
Three-phase gas relative permeabilities
Measured and predicted gas relative permeabilities for four experiments – gas into oil and water.
0.001
0.01
0.1
1
0 0.2 0.4 0.6 0.8 1
Gas Saturation
Gas
Rel
ativ
e P
erm
eab
ility
Experiment 8 (Measurements)
Experiment 8 (Predictions)
Experiment 9 (Measurements)
Experiment 9 (Predictions)
Experiment 10 (Measurements)
Experiment 10 (Predictions)
Experiment 20 (Measurements)
Experiment 20 (Predictions)
Three-phase water relative permeabilities
Measured and predicted water relative permeabilities for two experiments – gas into oil and water.
0.0001
0.001
0.01
0 0.2 0.4 0.6 0.8 1
Water Saturation
Wat
er R
elat
ive
Per
mea
bil
ity
Experiment 8 (Measurements)
Experiment 8 (Predictions)
Experiment 9 (Measurements)
Experiment 9 (Predictions)
Comparison of predictionsMeasured and predicted oil relative permeabilities compared to Stone 1 and saturation-weighted interpolation.
0.0
0.2
0.4
0.6
0.8
0 0.2 0.4 0.6 0.8
Measured oil relative permeability
Pre
dic
ted
oil
rela
tive
per
mea
bili
ty Network model
Stone 1(crosses) Saturation-weighted
interpolation (triangles)
Mixed-wet predictions - oil
Study the effect of wettability on three-phase relativepermeability. Gas injection into oil and water at fixedoil/water capillary pressure. Water-wet and ‘oil-wet.’
0.001
0.01
0.1
1
0 0.2 0.4 0.6 0.8 1
Oil Saturation
Oil R
ela
tive P
erm
eab
ilit
y
Water-wet
Oil-wet
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1
Gas Saturation
Gas
Rel
ativ
e P
erm
eab
ility
Mixed-wet predictions - gas
Water-wet
Oil-wet
Oil-wet gas relative permeability is lower than the water-wet case, since it is no longer non-wetting to water.
0
0.001
0.002
0.003
0.004
0.2 0.25 0.3 0.35 0.4 0.45 0.5
Water Saturation
Wate
r R
ela
tive P
erm
eab
ilit
y
Mixed-wet predictions – water
Water-wet
Oil-wet
Oil-wet water relative permeability is very low. Poorconnectivity of water after waterflooding.
Couple Couple ppore ore sscale cale nnetwork etwork mmodel to odel to a a 3D 3D ssimulator to imulator to ccapture apture displacement pathsdisplacement paths
Incorporation of multiple Incorporation of multiple displacementsdisplacements
Future Work
Conclusions
Developed a definitive three-phase Developed a definitive three-phase network modelnetwork model
Successfully predicts data from water-Successfully predicts data from water-wet and mixed-wet two-phase, and wet and mixed-wet two-phase, and water-wet three-phase experimentswater-wet three-phase experiments
Predicts mixed-wet three-phase Predicts mixed-wet three-phase properties – some surprisesproperties – some surprises
Where next? Extensive validation for a Where next? Extensive validation for a range of reservoir samplesrange of reservoir samples