Syed Umair Hasan (Masters of Science in Petroleum Engineering)
Conclusions and Recommendations
The Y-tool ESP system, a dual ESP configuration, represents a more recent approach adopted in the industry as an alternative to the single ESP system. It finds application in wells with closely spaced layers, where two ESPs work in tandem to achieve the desired well production and enhance the well operational lifespan.
A parametric design study on dual Y-tool ESP is conducted in this study using the steady-state commercial simulator PIPESIM. To simulate the Y-tool ESP structure, a connector is created as a Ytool junction, and two ESP wells are generated separately and connected to the connector. Then a flowline after the connector represents the wellbore. Parameters including reservoir pressure, production index, pump speed, water cut, GOR, viscosity, and pump design are investigated in this study. Results including production rate, Pump Intake Pressure (PIP), pressure distribution, boosting pressure, fluid properties, etc. are compared to evaluate the Y-tool ESP system design.
According to field data, two ESPs, namely REDA GN1300 and CENTRILIFT PH, are selected for the lower and upper layers. The Y-tool design is compared to the single ESP design as reservoir pressure declines, and its performance is parametrically studied. Then, the lower layer pump
REDA GN1300 is replaced by REDA D2150N, and the corresponding sensitivity analysis is conducted.
Y-ESP pressure envelopes are evaluated using single ESP nodal analysis and Y -ESP PIPESIM system analysis. In summary, reservoir property still dominates the two zone’s production behavior. A proper Y-tool pump design can help increase the system run lift and avoid one-layer early shutdown. Fluid properties also have some effect on the system. However, due to the PIPESIM ESP model’s limitation, only a qualitative study is conducted, and the real fluid property effect, i.e. viscosity, gas void fracture, emulsion inversion point, etc., should be investigated in the future study.