1 Enhanced Oil Recovery Studies in the Tirrawarra Oil Field, Cooper Basin, South Australia Ian Pedler 23 September 2009
Jan 12, 2016
1
Enhanced Oil Recovery Studies in the Tirrawarra Oil Field, Cooper Basin, South
Australia
Ian Pedler23 September 2009
2
Enhanced Oil Recovery Studies in the Tirrawarra Oil Field, Cooper Basin, South Australia
The Tirrawarra oil field is located in north-eastern South Australia in the Cooper Basin. The field was discovered in 1970 and is the largest onshore Permian oilfield in Australia. Primary production commenced in 1983 and from 1984 to 1996 the field was subjected to a miscible flood initially using raw satellite gas and subsequently, ethane injection. With the commencement of ethane sales from the Cooper Basin the EOR scheme was shut-down and the field was has been produced on blowdown since 1996.
In 2008 a study team was established to re-evaluate the field and review the potential for the re-establishment of and EOR scheme using CO2 or another suitable fluid with particular attention to the under-developed areas of the field. The study was an integrated review of the subsurface, well construction and facilities aspects of an EOR project and included the construction of a modern static reservoir model and fully compositional dynamic simulation model. This presentation will review some of the results from the 2008 study and the implications for the implementation of a future EOR scheme in the field.
3
Cooper Basin Unit Partners
4
Contents
1. Tirrawarra Field Review- Discovery
- Development
- Recent Performance
2. 2008 EOR Studies- Reservoir Modelling
- EOR Screening Results
5
1. Tirrawarra Field Review
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Tirrawarra Location
Queensland
NewSouth Wales
GunnedahBasin
GunnedahBasin
BowenBasin
BowenBasinCooper
BasinCooperBasin
SouthAustralia
Brisbane
SydneyAdelaide
Moomba
Santos acreage Basin outline Oil pipeline Gas pipeline
Pt Bonython
50km
7
Cooper Basin Operations
Typical Gas Wellhead Terrain Near Moomba
Tirrawarra SatelliteMoomba Plant
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Tirrawarra Discovery and Appraisal
1969 : First gas sales from Cooper Basin
1970 : Tirrawarra-1- Gas and oil discovery well
- TD 10,200 ft- Volatile oil in Tirrawarra formation
- 592 bopd max test rate- Liquids rich gas in multiple stacked
sands in overlying Patchawarra formation- 6.9 MMscf/d max test rate
1970 – 1972 Tirrawarra 2-11- Patchawarra/Tirrawarra
appraisal - Toolache formation gas discovery
1973 – 1979- No activity, pending
development of Cooper Basin Liquids Project
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Tirrawarra Field Summary
Tirrawarra Field Tirrawarra
Reservoir Properties
OOIP: 150 MMstbCrest : 9300 feet SSClosure : 550 feetThickness : 100 - 180 feetArea : 12,000 acresPorosity : 6 – 10%Permeability : 0.05 – 1 md
Fluid Properties
Initial Pressure : 4260 psiaBubble Point : 3000 psiaTemperature : 140 oCSolution GOR : 2700 scf/stbFVF : 2.7 rbbl/stbViscosity : 0.09 cP
Component Mol %
H2S 0.0
CO2 16.66
N2 1.72
Methane (C1) 31.95
Ethane (C2) 12.20
Propane (C3) 9.47
Iso Butane (iC4) 1.98
n-Butane (nC4) 3.72
Iso Pentane (iC5) 1.31
n-Pentane (nC5) 1.77
Hexanes (C6) 2.47
Heptanes+ (C7+) 16.75
100.00
API at 60oF 44.5
Tirrawarra Oil Composition
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Tirrawarra Field
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Tirrawarra Field Development
1981 : Commencement of Cooper Basin Liquids Project
1983 : First oil production from Tirrawarra (depletion)
1984 : Pilot EOR miscible flood project commenced based on raw gas injection- Total 10 Bcf inj from ’84-’88
1986 : Ethane injection commenced as part of basin ethane storage commitment
1997 : Ethane injection ceased with the commencement of ethane sales from the basin- Total 90 Bcf inj from ’86-’97
2007/8 : Multiwell appraisal programme and EOR Project Team established
TI15TI38
TI18
TI60
TI61
TI50
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Tirrawarra Field Production
27 MMstb produced to date
’84SG injection
’87C2 injection
’97 Cease Injection + Blowdown
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2. 2008 EOR Studies
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Current Operations
CO2 Remova
l
DeH2OLiquids Recover
y
Ethane Treatmen
t
Liquids to Pt Bonython
Ethane and Sales Gas to SydneySales Gas to Adelaide
CO2 to Vent
Moomba PlantCooper
Basin Gas Fields
Tirrawarra Oil Field
Tirrawarra
Satellite
Gas Satellite
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Proposed MCS1/EOR Project
CO2 Remova
l
DeH2OLiquids Recover
y
Ethane Treatmen
tCooper
Basin Gas Fields
Liquids to Pt Bonython
Ethane and Sales Gas to SydneySales Gas to Adelaide
Moomba Plant
De H2O Compression
New CO2 FacilitiesTirrawarra Oil
Field
Tirrawarra
Satellite
Gas Satellite
Upgrade
Upgrade
New Dense Phase Pipeline
New Inj & Prod Wells
New Fuel Gas Line
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Subsurface Workflow
Static Reservoir Model- First use of modern 3D reservoir
modelling tool in Tirrawarra- Integrate nearly 40 years of core,
log and stratigraphic data from >80 wells to create 3D geocelluar model- 120m x 120m x 1 ft (6,000,000 cells)
Dynamic Reservoir Model- Upscale Static Model to size suitable
for dynamic numerical modelling- 50,000 – 100,000 active cells
- Fully compositional reservoir model with 8 component PVT model
History Matching Process- Make ‘reasonable’ changes to a
base model to approximate past performance
- Matching >25 years of observed pressures, rates, ratios
- Iterative, time consuming & non-unique process
Outcome is a matched model that can be used to test various EOR and development scenarios
PetrophysicsStatic
Model
Dynamic
ModelUpscale
History Match
OOIP Sensitivities
New Dep. ModelPVT
Res. Eng. StudiesFracture / production / log KH / single well modelling etc
Feedback
Fieldwide Basic Data
Review
Appraisal Results Pr
oduc
tion,
Pres
sure
Dat
a
3D Seismic BasedStructural Interpretation
Matched Dynamic
Model to Test EOR and
Development Scenarios
SubsurfaceReservoir Modelling
ProductionFacilities
WellConstruction
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The Importance of Compositional Modelling
Comp. Mol %
CO2 16.66
N2 1.72
C1 31.95
C2 12.20
C3 9.47
iC4 1.98
nC4 3.72
iC5 1.31
nC5 1.77
C6 2.47
C7-C10
16.75C11-C16
C16+
Vent
Sales Gas
Ethane
LPG
Oil
3
1
2
4
5
678
Mol % Mol % Mol % Comp.
99.1 28.8 1.8 CO2
0.9 50.0 93.9N2
C1
- 13.4 3.9 C2
- 6.8 0.4
C3
iC4
nC4
1.0 - iC5
- - nC5
C6
C7-C10
C11-C16
C16+
Tirrawarra Reservoir
Fluid Prod
uct St
ream
Des
tina
tion
PVT
Com
pone
nt
EOR Injectants Studied
CO2
Sat. G
as
Sales
Gas
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Tirrawarra History Match - HCPV
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Tirrawarra History Match - Pressure
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Tirrawarra : Current Day Conditions
2009 HCPV 2009 Pressure
2009 StatusCore Area RF : 33%North Flank RF : 10%
Core, Brownfields AreaHigh on StructureLow pressure, swept
Northern, Greenfields AreaLower on structure,Higher pressure, unswept
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Tirrawarra : Current Day Conditions
2009 HCPV Reservoir kh
Core, Brownfields AreaHigh on StructureLow pressure, swept
Northern, Greenfields AreaLower on structure,Higher pressure, unswept
Core, Brownfields AreaGenerally higher kh and well productivity
Northern, Greenfields AreaGenerally lower kh and well productivity
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CO2 EOR Alternatives
600 ktpa CO2Greenfields Area“Oil Focussed” CO2 EOR52 New Wells•37 new prod•15 new injectors
600 ktpaBrownfields Area“Storage Focussed” CO2 EOR•no new wells, recreate original injection patterns
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Tirrawarra 600 ktpa CO2 EOR Cases
Net C5+ Production
0
2000
4000
2009 2014 2019 2024 2029 2034
bbl/
d
Net C5+ Production
0
2000
4000
2009 2014 2019 2024 2029 2034
bbl/
d
Net CO2 Production
-750
-500
-250
0
250
2009 2014 2019 2024 2029 2034
kT/Yr
Net CO2 Production
-750
-500
-250
0
250
2009 2014 2019 2024 2029 2034
kT/Yr
CO2 Balance
0
500
1000
2009 2014 2019 2024 2029 2034
kT C
O2
Produced CO2
Injected CO2
CO2 Balance
0
500
1000
2009 2014 2019 2024 2029 2034
kT C
O2
Produced CO2
Injected CO2
Brownfields Area“Storage Focussed”CO2 EOR
Greenfields Area“Oil Focussed”CO2 EOR
Incremental Recovery
0
10
20
30
Oil EOR S'age EOR
MM
boe
Oil
LPG
C2C1
Oil
CO2 Storage
0
5
10
Mt CO
2
Tota
l In
j.
Tota
l In
j.
Net
S’a
ge
Net
S’a
ge
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The Fuel Gas Challenge …..
Capture Process Compression
Moomba Plant
1 Mtpa CO2 to EOR
1 Mtpa CO2 to Vent
Sales Gas
100 ktpa CO2 to Atmosphere
Gas Turbine
•To inject 1 Mtpa of CO2 for EOR, 0.1 Mtpa of new CO2 emissions are generated. For EOR, CO2 is cycled through the reservoir and plant several times and each time this happens new CO2 emissions are generated.
•For pure MCS this only happens once
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The Fuel Gas Challenge …..
Capture Process Compression
Moomba Plant
1 Mtpa CO2 to EOR
1 Mtpa CO2 to Vent
Electric DriverGeothermal
Power Station
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EOR Fluid Evaluation
0%
10%
20%
30%
40%
0.0 0.5 1.0 1.5 2.0 2.5
HCPV of EOR Fluid Injected
Incr
em
enta
l Reco
very
Fact
or
CO2
Satellite Gas
Sales Gas
Initial Depletion Phase
Sales Gas Blowdown
Satellite Gas Blowdown
Basis:Greenfields AreaNorthern Injection Only600ktpa CO2(e)
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Conclusions
Pre FEED Studies successfully completed in early 2009
Cooper Basin JV has chosen to place a large scale Tirrawarra CO2 EOR project on hold pending clarity on carbon pricing and oil price recovery
New development drilling in Northern Tirrawarra is proposed for 2010 to prove reservoir performance of this area
Australia’s only EOR Project is currently underway in nearby Fly Lake field- Pilot scale project using Tirrawarra satellite gas to increase
oil recovery
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Acknowledgements
TEOR Subsurface Pre-FEED Team- David Grybowski, Bich Thuy Ngo Hoang, Adam Little,
Serge Toulekima and Alan Waldron
Cooper Basin Joint Venture Partners