Method and apparatus for producing a well

摘要

A system and method for producing earth formation fluids such as crude oil using a lighter oil to force the crude oil to the surface and thereafter removing the lighter oil by gas lift techniques. The well system includes spaced packers defining a production chamber in the well bore, a production tubing extending through the packers having check valves and ports for well fluids to flow into the chamber from below the packer while isolating the chamber from the pressure of production fluids in the production tubing. Power fluid tubing extends through the upper packer into the production chamber including spaced gas lift valves and gas flow means from the lowermost gas lift valve into the production chamber. Surface equipment is provided for pumping power fluid into the power fluid tubing string, introducing lift gas into the power fluid tubing string above the upper packer, and separating returned power fluid and lift gas. In the method, formation fluids flow into the production chamber under formation pressure, power fluid is pumped into the chamber displacing the formation fluids through the producing string, and the power fluid is removed from the production chamber and power fluid tubing by lift gas.