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This paper discusses the experience and lessons learned during three years of electrical submersible pump (ESP) operation in heavy and viscous oil in the Peregrino field. Artificial lift applications on heavy oil fields have been a challenge for operators, and the Peregrino field is a good example for this type of ESP application.An ESP was designed to enable a wide operation window to fulfill reservoir conditions changes and to focus on the extended run life and overall lifting efficiency. Three different ESP configurations were applied to produce liquid rates from 1500 to 20000 STB/d utilizing 1100-HP and 540-HP motors. Upper completions using a packer and capsule solution were selected to comply with all production conditions. Peregrino field is a Statoil asset located in Campos Basin, approximately 85 km offshore from Cabo Frio/Rio de Janeiro state in Brazil. The oil in Peregrino has viscosity between 129 cp to 364 cp, and the API gravity varies between 13°and 15°API. The first phase of field development comprised two drilling-capable wellhead platforms and a centrally moored FPSO. Currently, there are 27 producer wells, including 3 multilaterals and 6 injectors in operation. The field is currently producing close to 100,000 STB/d of oil and has achieved a production record of 104,292 STB/d in July 2013.The learning and experience developed from the ESP design phase through three years of operation represents a very important set of best practices. This information can be used by the industry as a complete field-proven method of ESP project implementation, particularly when dealing with high flow rates, high horsepower, and viscous oil ESP operations in an offshore environment.

Peregrino is a Brazilian offshore field which has been operated by Equinor since 2011. The fields crude oil viscosity ranges from 129 to 364 cp and the API gravity varies between 13° and 15° API. Electrical Submersible Pumps (ESP's) were selected as the Artificial Lift method to produce the heavy oil from Peregrino. The ESP equipment design has been modified throughout the years to address various failure modes, therefore improve system reliability by adapting customized solutions. This paper describes in detail the ESP application and solutions implemented in the field to overcome those challenges. Every ESP string pulled from Peregrino is dismantled and inspected and this paper will discuss the routines used to conduct failure analysis and continuous improvement. The main challenge with the ESP operations in Peregrino has been asphaltene precipitation in the seal sections and emulsion formation. Emulsion instabilities cause pressure, temperature and electrical current fluctuations, which increase stress in downhole equipment. This paper will discuss how the ESP equipment in Peregrino has been improved to meet the various challenges, an overview of the following equipment changes will be discussed:Packer penetratorPump diffusersESP MotorNew Seal construction An overview of the ESP equipment reliability spanning the lifetime of Peregrino's operations will also be described in this paper.