Gas Well Deliquification

Gas Well Deliquification
Werner Schinagl and Matt Dunning
DEVEX 2009
Presentation Outline
•  Short Overview of Liquid Loading
•  Initial Steps
•  Current situation
•  Future (Matt Dunning)
2
Liquid Loading
•  “Liquid Loading is the Inability of a gas well to produce liquids
to surface”.
•  Historic production losses in BP in Gas Fields caused by
liquid loading: around 15% of production potential globally
3
Initial Steps
•  Soap Sticks:
−  No success:
−  Not enough concentration (too few sticks)
−  Wrong chemistry?
−  Soap sticks in highly deviated wells?
•  Velocity Strings:
−  Very successful where installed in RIGHT wells
−  However, complex operation on small platforms
4
Initial Steps
•  Batch Surfactant Treatments (2006): Great Success
−  Increase in time online
−  Increase in drawdown and production rates
5
Initial Steps
•  Foaming success in SNS, CNS lead to more “risky”
applications:
−  Condensate foaming in Sharjah: success with new
condensate foamer (Offshore Europe presentation)
−  Attempt to foam condensate in predominantly condensate
well by using a water foamer and diluting CWR with water
injection
−  NO success but also no well-kill
6
Current Situation
•  Batch foaming success led to development of 5 “permanently
installed” surfactant skids
−  Challenges:
−  Operations on NUIs
−  Benefit measure limited to temperature correlations
7
Well 1
Surfactant
Injection
8
Well 2
Surfactant
Injection
9
Well 3
Surfactant
Injection
10
Challenges in Implementation
•  Infrastructure and Environment
−  Terminal Compatibility
−  Oil in water issues
−  Separator settings
−  Disposal of surfactant treated water
•  Operational
−  Training of offshore staff
−  Time on platform/priority of work
−  Chemical Storage and Transport
11
Summary and Conclusions
•  Surfactant Injected on 2 platforms
−  Benefit realized this year (up to 1H08)
−  P1 = 0.13 mboe/d (2 wells)
−  P2 = 0.17 mboe/d (2 wells)
−  Estimated benefit of continue surfactant batching
−  P1 = 0.4 – 1.7 mboe (5 wells)
−  P2 = 0.5 – 1.5 mboe (5 wells)
−  Recommendations
−  Install automated surfactant injection system
−  More offshore emphasis/importance on surfactant
12
Future Steps
13