摘要 |
A gas-lift apparatus and method for use in a well in which liquids accumulate in a liquid zone. The apparatus comprises a first string extending into the liquid zone and having upper and lower ends; a second string surrounding the first string and defining an annulus therewith, the second string extending a distance from the first string lower end such that the annulus has upper and lower ends, the annulus being closed at its upper and lower ends and defining a chamber, the chamber being in fluid communication with the inside of the first string; a check valve controlling the flow of liquid into from the wellbore into the lower end of said annulus; a gas valve allowing the flow of gas from the first string into the upper end of the chamber; and a valve for controlling the flow of gas into the upper end of said inner string. |