1. Predicting Future Gas Lift Performance in a Mature Water Flooded Field
ASME/API Gas-Lift Workshop
12 – 13th November 2001
Aberdeen, Scotland
Predicting Future Gas Lift
Performance in a Mature
Water Flooded Field
Tony Liao & Simon Bishop, BP

2. Miller Field

3. Location of Miller Field

4. Miller Field Background
Discovered in late 1982
Oil was found 4,000 meters beneath the seabed in a water depth of 100 meters
The field lies 270km NE of Aberdeen
Estimated 240 million barrels of recoverable oil and 480 billion cubic feet of associated gas

5. Miller Field Background
Oil production commenced in May 1992
Gas production following about two months later
Brae field has been on production since 1983
Reservoir pressure in Miller has declined while Brae has been produced

6. Objective
Predict performance of Miller field if 4 of 9 naturaly flowing wells are converted to gas lifted
Provide BU and partners performance data to make production management decision

7. Study Methodology
Match production & injection history of Miller field
Integrate reservoirs, wells, and surface network in a completed system
Tune well models against well test data
Generate vertical lift performance (VLP) curves for all naturally flowing & gas lifted wells
Generate well IPR curves
Generate well performance curves based on VLP & IPR curves
Predict field performance under different operation strategies and system constraints

8. Miller Field Schematic

9. Multi-Reservoir Model Consideration
Pressure data showed distinct trend in each compartment
Geological description clearly supported a multi-tank system
Single tank Mbal model was tested but history match was not as good

10. Miller Multi-Reservoir Mbal Model

11. History Matching: Southern Tank

12. Simulation

13. Application of Integrated Model
Forecast production from every well, every tank, and the entire reservoir
Forecast water injection to each tank
Evaluate the impact of converting certain wells to gas lift at a specified time

14. Miller Integrated Model: Production Forecast

15. Gas Lift Well Performance Curves

16. Application of the Integrated Model

17. Application of Integrated Model

18. Conclusion
Converting four wells from naturaly flowing to gas lifted will be beneficial for the Miller field
Cumulative oil production incremental is 1 MMB over 4 years
Integrated study provided Miller Business Unit with technical results required for reservoir management decision