Publications

Continuous gas lift (CGL) is not appropriate for installation in low influx (PI <, 1) and gassy wells (GOR > 2000 scf/stb), since excessive gas injection will result in back pressure in the tubing, leading to the well ceasing to flow. Hence, in order to keep producing low influx wells, we need a method to inject a sufficient amount of gas into the well required. Intermittent gas lift (IGL) is a modified version of CGL. It has shut-in (SI) and producing time, called cycle. Instead of injecting gas continuously for 24 hours, IGL will only inject according to the input time cycle. For example, if we have 3-1 SI and producing cycle the gas will only inject for one hour every 4 hours. SI time, also called build-up time, is the time required by the reservoir to fill the wellbore with its influx. 8 IGL wells in Kaji, South Sumatra, have contributed approximately 105 BOPD oil gain. In addition, gas injection consumption has been reduced by up to 50%. Converting a CGL well to IGL only requires installation of an IGL controller in the gas lift line at the surface, while the downhole equipment remains the same. It has a control valve which will open and close according to the setting time cycle. When the valve opens to inject gas through the annulus it is called producing time. If producing time comes to an end, it will automatically close and prevent gas from injecting the wellbore. At the same time, this closing action also gives the reservoir enough time to fill thewellbore with its influx, so that liquid can build up along the tubing. The implementation of this method has proven benefits, therefore it is desirable to install IGL in other low influx and gassy wells.