Influence of wellhead pressure and water cut in the optimization of oil production from gas lifted wells

The worldwide increase in energy demand necessitates the development and optimization of marginal oil fields for sustenance. In this regard, effective and economic production of fluids are heavily relied upon the artificial lift techniques as the reservoir's natural energy may not be able to deliver the fluids to the surface. Gas lift is a widely practised and successful method that is suitable for rejuvenating the oil production from such fields. In this study, the influence of critical parameters like water cut, wellhead pressure(WHP) and gas-lift gas injection rate on the output from a gas lifted well was analysed. A significant reduction in the oil production was observed with the increase in water cut. For a fixed gas injection rate of 1 Mmscf/day, the production decreased by 26.90% when the water cut increased from15% to 30% and further by 50.80% when the water cut reached 45%. An increase in the gas injection rate from 1 Mmscf/day to 8 Mmscf/day resulted in an increase in the production rate by 29.21%, 40.48% and56.56% for 15%, 30%, and 45% water cut conditions, respectively. It was observed that there is a drop in the oil rate with the increase in WHP for a constant gas injection rate. An increase in the WHP from 100 psi to300 psi resulted in a drop in the oil production rate by 11.01%, 11.78% and 12.74% for 15%, 30% and 45%water cut conditions, respectively. The study sheds light on the significance of optimizing the critical parameters to maximize the production from a well, with severely affected productivity, using a continuous gas lift system.