Economic Evaluation of Electrical Submersible Pump (ESP) and Gas Lift Well For Production Optimization in A Niger Delta Field

Gas lift system and Electrical submersible Pump’s (ESP) are few of the artificial lift methods used to start up a well and or increase the producing life of oil / or gas wells. The principle of Gas lift is by lowering the hydrostatic pressure inside the production tubing through the injection of lighter fluid into the annulus. While the ESP gives an external pressure to the flow stream acting in series with the reservoir. GT oil field in the Niger Delta was used as case study, it has a production life span of eighteen 18 years. To increase GT production and extend the lifetime of the field, the operator decided to start an artificial lift project with an aim to optimize its production. To select the best artificial lift method to use, an economic evaluation was carried out using PROSPER for gas lift, ESP and a base case (Natural Flow) and then a production forecast with the different scenarios was done for six years. In technical comparison, PROSPER simulation results shows that both Gas lift techniques and the Electrical Submersible Pump (ESP) gave a higher production rates when compared with the Base Case (Natural Flow), and in terms of economic comparison, ESP generated the highest gross profit, but considering other factors like: water cut and replacement of failed pump, gas lift system was preferred for proper production optimization techniques. Hence, result from ESP indicated a faster reservoir pressure depletion and water encroachment. However, gas lift was chosen for GT based on the availability of readily compressed gas, higher life time expectance and lower installation and operational cost as compared with the ESP which had the highest production potential.