Optimization of gas lift system for well performance improvement in Asmari formation: A techno-economic perspective

Abstract

Well productivity in the Asmari carbonate formation of southwest Iran has decreased in recent years as a result of production issues. The production rate must be maintained below 1500 STB/day to prevent water coning. In this study, a gas lift well is modeled using data from one of the producing wells of this field. Nodal analysis is performed using lift-gas injection rates and wellhead pressures at different reservoir pressures and water cut conditions to optimize production. Economic aspects are considered to optimize the artificial gas injection rates at different tubing head pressures and water cut conditions. Increasing the lift-gas injection rate from 0.4 MMscf/day to 1 MMscf/day enhances the oil production rate by 37.71% and 43.89% for 10% and 30% water cut conditions, respectively. Gas injection rates of 5.2 MMscf/day and 5.4 MMscf/day are determined to be economically optimal for 30% water cut with tubing head pressures of 260 psig and 270 psig, respectively.