GAS LIFT
Application:

Gas lift is the method of artificial lift for producing oil and gas wells that do not have the natural energy to deliver liquids to the surface at desired rates.  This method of lift most closely resembles the natural flowing well.  In both the flowing well and the gas lift well, the energy stored in natural gas under pressure is utilized to bring fluids to the surface.  Compressed gas expands on the way to the surface, reducing fluid density and column weight of fluid.  This process reduces the flowing tubing pressure creating a differential pressure between the reservoir and the well bore allowing the well to flow.

• Can produce almost any oil or gas well that requires artificial lift.  Gas lift is limited only by the availability of gas.
• Can be used to unload and kickoff wells that flow on their own.
• Gas lift can increase the rate of some flowing wells.
• Can be used to increase the velocity in a gas well to assure produced fluids are recovered at the surface.
• Large tubing or annular lift can be utilized to produce extremely high rates.
• Intermittent lift can be used to produce wells with low production rates or low reservoir pressure.
• Sidepocket gas lift mandrels can be run with dummy valves in the initial completion when the well may flow on its own.  Later, when the well has loading problems, gas lift valves can be installed with wireline to produce the well at its optimum rate.

Advantages:

• Gas lift installations can generally handle the flowing conditions throughout the life of the well.  Changing reservoir pressures, water cuts and formation gas rates can be taken into account with the initial design.
• Gas lift equipment is durable and has few moving parts.  A longer life can be expected compared to other means of artificial lift.
• Low initial installation cost.
• Low maintenance cost.
• Operator can control production rates from the surface.
• Produced sand has little effect on gas lift equipment.
• Gas lift is not adversely affected by wellbore deviations.