Perpustakaan Digital ITB

The gas lift type of artificial lifting technique is currently used in several old fields in Indonesia. Gas lifts have up till now been widely applied throughout the world, not just in Indonesia. The fact that this approach may be applied to wells with deviations, in addition to wells of any depth, and the generally inexpensive cost of lifting for a large number of wells, are some of its benefits. The presence of flow instability, which can result in compressor shutdowns due to pressure surges and fluid flow rates, in one of the issues that frequently arises in gas lifting operations. A set of criteria will be used to pinpoint this instability problem so that adjustments may be made during the design phase. Furthermore, the stability results will be classified based on the flow pattern using mechanistic modeling, namely the flow pattern map. In this case study, several wells in field X, an offshore oil field in the northern Java Sea, was the focus of the study. The majority of wells in this field have gas lifts installed as a means of artificial lifting technique. The chosen field has a high Productivity Index value as well as a high injection flow rate. Historical data on production and wells in 2016 were then used into calculations to determine the stability of gas lifts by method Asheim and Alhanati. Furthermore, from the results of the stability will be grouped what flow patterns are occurring. The objective of this study was to discover the most effective approach for assessing the stability of a gas lift. The Alhanati approach is preferred above the Asheim method, according to the results of calculations made using the available data and both methodologies. Based on literature studies, the flow pattern for stable conditions is slug, churn, and dispersed bubble, while in unstable conditions it is dispersed bubble. The flow pattern obtained from field data X for stable and unstable condition is churn.