To Design a Continuous Gas Lift Method for Improving Production in a Dead Well: A Case Study

Abstract

In Petroleum industry the goal of production department is to obtain maximum oil production at minimum expenditures. The oil production from the wells decreases after some period due to decline in reservoir pressure, increase in water cut, water conning etc. in other words the revenue is lost. Therefore, the artificial lift system is installed on the wells depending upon its characteristics. Gas lift system is one of the most popular artificial lift systems to optimize oil recovery employed in petroleum industry. In gas lift system, gas injected into the well through gas lift valves which reduces the density of liquid column in the well which in turn causes the oil to be produced at the surface. This research study is conducted on well named A-1 in an onshore field Alpha, the well is considered dead due to increase in water cut (40%). The objectives of this research study are to unload the well by designing an efficient continuous gas lift method and then optimize the production by varying some parameters. For this purpose, a simulation model of base case well and gas lift case is designed on PROSPER software by entering the PVT properties, well properties and reservoir properties. After that a sensitivity analysis is performed on PROSPER by changing some variables such as; water cut, wellhead pressure, skin factor, gas injection rate and casing pressure. Subsequently designing the model of the well with gas lift method the well started to produce oil at suitable rate. After that the production is optimized by performing sensitivity analysis on some variables and optimum oil production rate vs gas injection rate is obtained.