Deliquefy a Deep Gas Well with a Recirculation Electric Submersible Pump System

As a gas well dewatering artificial lift system, the electric submersible pump (ESP) is prone to gas interference, leading to such failure such as gas lock. Effective gas separation is essential to the efficient operation of ESPs. However, current studies do not concern the calculus of motor cooling. Taking a deep gas well in the Tarim Basin as a case study, this paper designs an inverted shroud to separate gas from well fluid. To analyze the workings of the inverted shroud, an equivalent virtual well is set up in a commercial software. The predicted pump intake and discharge pressures from the simulation are in good agreement with measurements from downhole sensors, proving high efficiency in gas separation with the inverted shroud, while also lending confidence to further studies. To improve the cooling of ESP motor seated below the shroud, a recirculation ESP system is also proposed. Numerical simulations indicate that two capillary tubes with an inside diameter of 10.5 mm are sufficient for motor cooling. These findings are helpful to boost ESP applications in deep gas well deliquifications.