TOETOHEEL DISPLACEMENT PROCESSES

1
Emerging Oil Recovery Technologies
TOE-TO-HEEL DISPLACEMENT PROCESSES
Presenter Alex Turta Alberta Research Council
(ARC)
Presentation to CHOA, October 12th, 2005
2
DISCLAIMER
Nothing in this presentation shall in anyway
state or in any way imply that ARC is endorsing,
approving, recommending or giving any warranties
related to any of the matters referred to in the
aspect of the Toe-To-Heel Air Injection (THAI)
Technology.ARC makes no representation or
warranties, either expressed or implied, as to
any matter including, without limitation, the
condition, quality or freedom from error of the
data, information, analysis and conclusions
contained within this presentation.
3
Outline

• Introduction
• Short-distance and long-distance oil displacement
• Short-distance oil displacement processes
• - CSS, SAGD, Vapex and Toe-To-Heel (TTH)
• Thermal and Non-Thermal TTH Displacement
  processes
• Field Testing of TTH Processes

4
Long-distance Short-distance Oil Displacement
Processes
5
SDD Processes Cyclic Steam Stimulation (CSS),
SAGD, Vapex

• CSS commercially developed as a stimulation
  method using mainly vertical wells 5-20 m - the
  distance the fluids are flowing
• SAGD/Vapex flowing distance 20-40 m
• Note Compared to 200-400m in the LDOD processes.

6
SAGD
Steam Chamber
Horizontal Injector
Oil with reduced viscosity drains
Unswept zone
Horizontal Producer
7
TTH Displacement Processes

• A) Thermal TTH processes
• Development of THAI CAPRI collaborative effort
  between U of Bath (UK) Petroleum Recovery
  Institute (nowARC)
• THAI CAPRI technologies acquired by Petrobank
  Energy and Resources of Calgary
• B) Non-thermal TTH processes
• Toe-To-Heel Waterflooding (TTHW) gravity stable
  process developed by PRI ARC

8
Novel Thermal Recovery Processes
THERMAL TOE-TO-HEEL PROCESSES (THAI / CAPRI)
9
Conventional In Situ Combustion (ISC)
Air, Air H2O, etc.
Reaction zone
Combustion zone
Oil banking in the cold region
Cool zone
Swept zone
University of Waterloo
( Courtesy of M. Dusseault)
10
Stability Problems of Conventional ISC (Heavy Oil)
Oil bank
Relative gas permeability
HTO
LTO
11
Toe-To-Heel Air Injection Simplest Well
Configuration, Staggered or Direct Line Drive.
Birds Eye View
12
Schematic of Toe-to-Heel Air Injection
Mobile oil zone (MOZ)
Producer well
Combustion zone
Injection well
Coke zone
Air
Cold Heavy Oil
Toe
Heel
13
Schematic of CAPRI Process
SCHEMATIC OF CAPRI PROCESS
14
Differentiation of THAI

• To avoid the flow of oil through the cold region,
  involving
• - either exceedingly high pressure drops
  (drastic reduction of the air flux / injectivity
  problems)
• - or a direct channeling of the ISC front.
• To reduce severity of the negative effect due to
  reservoir heterogeneity (stratification effects)

15
THAI Configuration and Operation

• Line drive operation (2 phases)
• Initiation of a quasi-linear, in-situ
  combustion (ISC) front and its anchoring at the
  toe of horizontal producer (with or without hot
  communication)
• ISC front is propagated from the toe to the heel
  of horizontal producer

16
Combustion Front
Propagation of
in THAI
Coke Zone
Mobile Oil Zone
Injection well
Producer well
Air Water
Cold Heavy Oil
Toe
Heel
17
Some Potential Benefits of THAI
18
THAI Summary of Work (since 1992)

• More than 70 laboratory tests conducted in 3D
  models by University of Bath, UK
• Simulation conducted by several organizations
• - Lab scale
• - Field scale
• Field piloting to start in 2006

19
Variation of the thermal upgrading during dry and
wet THAI using Wolf Lake oil (viscosity 50,000
mPa.s)
Viscosity of produced oil 10,000 mPa.s
Laboratory tests
Courtesy of U. of Bath, UK
20
Thermal and catalytic upgrading of produced
oil in THAI process for Athabasca tar sand.
Run 2000-01
Run 2000-02
Catalytic THAI (CAPRI)
THAI
API Density of the Produced Oil
Oil visc 1 million ? THAI ?1,000 ? CAPRI ? 50
Courtesy of U. of Bath, UK
Laboratory tests
21
Numerical Simulation of THAI

• CMG
• ARC
• U. of Bath
• Petrobank Energy and Resources Ltd.
• Note (CMGs STARS simulator was used)

22
Field Testing of THAI

• (Whitesands Project, Conklin, Alberta)
• To start in 2006

23
THAI PILOT LOCATION
Courtesy of Orion Oil, Canada
24
Field Testing of THAI
Phase I Wells
Phase II Wells
Combustion Front
Courtesy of Orion Oil, Canada
25
Non-thermal TTH processes

• Toe-To-Heel Waterflooding (TTHW) Technology

26


TTH Waterflooding Process
Vertical injector Horizontal producer

Brine Sp.Grav. gt1.0



27
TTHW Using Vertical Injectors. Well
Configuration. Birds eye view
vi
vi
TOE
Horizontal well producer
HEEL
28
TTHW Applied with Horizontal Injectors. Well
Configuration
T
T
H
H
vi
vi
TOE (T)
Horizontal producer (HP)
HEEL (H)
29
(No Transcript)
30
TTHW Summary of Work (since 1996)

• Hele Shaw tests 2-D model tests
• 3D model tests
• Simulation
• - Lab scale
• - Field scale
• US and Canadian patents (ARC owned)
• Start of field piloting

31
TTHW in a Hele Shaw Model. Water invaded zone for
a light heavy oil (780 mPa.s), before watering
out (tape 19)
32
Bodo oil (viscosity - 12,000 cp) Water invaded
zone at watering out stage
33
TTHW Using Vertical Injectors Lab Well
Configuration. Birds eye view
vi
vi
TOE
42 cm
Horizontal well producer
HEEL
27 cm
34
3-D Model OIL RECOVERY for TTHW AND CONVENTIONAL
WATERFLOODING
Homogeneous rock
780 mPa.s OIL
Oil recovery (fraction of OOIP)
TTHW
Conv. WFLD
35
Simulation of 3-D TTHW Lab Test Water Saturation
at 2 hrs
780 mPa.s OIL
Mid vertical plane
36
Simulation of 3-D TTHW Lab Test Water Saturation
at 50 hrs
780 mPa.s OIL
mid vertical plane
37
TTHW field application well layout and operation
38
(No Transcript)
39
(No Transcript)
40
TTHW application with horizontal wells drilled
in a pad
41
Potential Benefits

• Immediate oil production
• More forgiving relative to quality of injected
  water and operation (interruptions in water
  injection not so harmful !)
• Reduced sensitivity to reservoir heterogeneity
  and unfavourable mobility ratio
• Better control of operation due to progressive
  watering out from toe to heel

42
TTHW Field Testing in MHGC

• TTHW field pilot is under way
• Collaborative Development and Licence Agreement
  between ARC and EnerPLUS RESOURCES FUND to test
  TTHW at Medicine Hat Glauconitic C (MHGC) Field
• Several TTHW patterns several years of testing
• Oldest TTHW patterns have been running for more
  than 3 years

43
TTHW Criteria for Field Application

• No gas cap
• Pay thickness gt 6m
• Oil viscosity lt 2,000 mPas
• Oil saturation gt 50
• Current water-oil ratio lt 10
• Horizontal permeability (KH) gt 200 mD
• Vertical permeability (KV) gt 100 mD

44
The last two conditions are relaxed when

• Horizontal permeability (KH) increases downwards
  (finning upwards)
• There is a high perm. streak at the bottom of the
  pay
• Weak bottom water situations

45
END
Did we make GRAVITY fully work on our
advantage?