Shell UK Exploration and Production Monday 12 November 2001 Sub-Sea Gas-Lift Session 1. Chevron’s design philosophy (Ken Decker) 2. Equipment for GL in deepwater (Roger Stinson) 3. Reducing well-test deferments (Philip Holweg) 4. GL as back-up of ESP lifted wells (Eric Lovie/ Philip Holweg) Sub-Sea GL Panel Session (Wim der Kinderen) Shell UK Exploration and Production

Shell UK Exploration and Production How can we eliminate or alleviate limitations of sub-sea gas-lift ? Shell UK Exploration and Production

Shell UK Exploration and Production Subsea Gas-Lift Issues Expensive well entries Compromised lift depth Compromised injection port size Gas-lift optimisation is difficult but critical Limited or no survey and well test data available Subsea GL flowmeters are unreliable GL flow control is effectively choke position control Unloading valve failures are difficult to identify Cold lift gas may cause hydrate problems Leaking check valves jeopardise well integrity Shell UK Exploration and Production