Gas-lifted production is essentially artificially enhanced natural flow. It is a viable unloading solution for wells with higher-volume liquid production when a convenient source of high-pressure lift supply gas is nearby. Gas lift has the advantage of being able to work unobtrusively in wells with deviation, solids production and subsurface safety valves.

Lift gas can be injected continuously into the production stream to maintain gas velocity so that the well can continue to unload liquids. Alternatively, intermittent gas lift is a cyclic form of lift used to unload lower-pressured reservoirs. It can be combined with plunger lift to form a hybrid-lift system to improve conventional intermittent-lift efficiency or to operate a plunger-lift system where additional energy is required.

Remedial Gas-Lift Installation

A low-cost method of applying gas lift is the orifice insert. An orifice “button” is inserted into the tubing string, using a simple wireline procedure. The insert provides a single-lift point to unload fluids in the early stages of liquid loading.

Concentric packoffs offer a remedial gas-lift system with multiple injection points to extend the life of a loaded gas well without rig-based intervention and allow for deeper injection depths to achieve liquid removal at lower bottomhole pressures.

Annular Flow and Coiled-Tubing Gas Lift

Injecting gas down the tubing string and into the annulus to lift a well eliminates packers, mitigates mechanical risk and is especially effective in slimhole monobore wells. Coiled-tubing conveyance of the annular flow system is another common adaptation of this form of gas lift and is relatively inexpensive in comparison to rig-based workover operations.

Xtra-Lift™ Gas Lift

The Xtra-Lift application uses conventional gas-lift equipment with a bypass packer and a dead string to reduce flow areas so that flow velocity rises to improve the overall unloading capacity in the well. If you have conventionally cased wells with extremely long perforated intervals and a convenient source of high-pressure lift gas nearby, the Xtra-Lift system may be a viable approach.