This paper provides field experience for the Caisson ESP Technology in subsea boosting system with emulsions and high Gas Volumen Fraction (GVF) using the high power Electric Submersible Pumps (ESPs) systems. Field experience and experimental performance are compared regarding the effects of high viscous emulsion using conventional high capacity ESP systems and the effect of two phase (liquid & gas) fluids on ESP with new technology for high GVF fields and high viscous applications.
The Electrical Submersible Pump (ESP) system is an important artificial lift method commonly used for subsea boosting systems. Multiphase flow and viscous fluids cause problems in pump applications. Free gas inside an ESP causes many operational problems such as loss of pump performance or gas lock condition. The objective of this paper is to understand MVP performance for high GVF and viscous emulsions.
This paper provides a summary on the performance comparison for a high power ESP system for viscous emulsions and Multi-Vane Pump (MVP) for high GVF wells for Shell major Projects BC-10. These novel projects continue the long tradition of Shell’s leadership in the challenging deepwater environment. Presented is the capability and effects of viscosity and two phase (liquid & gas) fluids using a 1025 series pumps with a charge MVP in series; as well as a 875 series standard ESP system mixed-type pump, which is a multistage centrifugal pumps for deep boreholes.
Extensive testing and qualification of the subsea boosting system was undertaken prior to field application. The subsea boosting system experience for offshore operations is reported with new technology, and the effects of viscosity and two phases in real conditions. MVP and high power pumps were proved to be a reliable technology to use in field application managing GVF higher than 50% and high viscous fluid as high as 1200cp as consequence of fluid emulsion. Correction factors needed to be applied to standard design curves to ensure proper field design at opearting conditions.