An Assessment Approach for Optimization of Gas Lift Performance in a Malaysian Oil Field

Abstract

Among all the artificial lift methods, gas lift known to be cheap and could be utilized in both
onshore and offshore. Gas lift mechanism depends on crude density reduction and hydrostatic pressure
minimizing. Despite, the great advantage of gas lift method, the results varies based on the case examined.
Some critical factors as gas specific gravity, appropriate gas selection reservoir pressure cannot be
generalized. This research focuses on well-X case. The study used Prosper software to evaluate each gas by
its specific gravity. Furthermore, the generated model and data input were verified to ensure the accuracy.
The results of the study revealed that there was no fluid flow before the gas lift operation. All the gases
studied revived well-X. The significant result was the ability of CH4 to achieve the highest oil production of
2023 STB/ day at injection rate of 4.2 MMSF/day. The lowest reservoir pressure that allowed the gas lift to
maintain the performance was 1000 psi. The economic range found to be [(2-4.2), (2-3.6) and (1-2.7)]
MMSCF/D for CH4, N2 and CO2 respectively. That leaded to an economic injection rate of 3, 3.4 and 2.4
MMSCF/D for CH4, N2 and CO2 correspondingly. The research was limited by the lack of the available data
of well-X, especially to address the corrosion impact of the gases. Finally, the findings contribute to the oil
and gas by considering greenhouse gasses. Also, it recommends the possibility of using hybrid injection
technique for well- X along with considering the effect of additional water cut.