In-Well Dual Canned ESP Completion Test To Validate Safe Deployment in Deep Water

Abstract

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper OTC 26002, “Testing In-Well Dual Canned ESP Completion System To Validate Safe Deployment in Deep Water: A Collaborative Effort To Understand Surface and Downhole Requirements,” by Kim Tijerina, Baker Hughes, and Carlos Pardo and Andy Hope, Chevron, prepared for the 2015 Offshore Technology Conference, Houston, 4-7 May. The paper has not been peer reviewed. Deepwater and ultradeepwater completions use numerous hydraulic control lines for control and actuation of downhole equipment. Incorporating a completion system with an in-well lift such as electrical submersible pumps (ESPs) increases the number of electrical lines needed. This paper discusses the planning and execution of a stack-up test (SUT) to determine whether a completion system incorporating a dual canned ESP system with multiple control lines can be deployed efficiently and safely in a deepwater, high-pressure/high-temperature (HP/HT) environment. Introduction Lower Tertiary Play Characteristics and Challenges. Fields in the Lower Tertiary play, also known as the Paleogene, have low porosity (15–25%) and low permeability (<10 md), which reduce the amount of oil that can be recovered without assistance. In addition, Lower Tertiary water depths range from 5,000 ft to more than 10,000 ft; reservoirs are deeper than 26,000 ft; pressures range from 25,000 to 30,000 psi; and temperatures can be higher than 300°F, further complicating production. The Wilcox formation lies in the Lower Tertiary and is divided into the Upper, Middle, and Lower Wilcox on the basis of each section’s stratigraphy. The Lower Tertiary formations can produce large volumes of oil and gas, assisted by high pressure within the formation. However, as the reservoir pressure depletes, adequate production rates cannot be maintained without effective reservoir-pressure maintenance or artificial lift. In shallow-water wells, gas lift assistance has been used and proved effective for production but requires a large gas supply and infrastructure to support production. Another proven technique used for fluid-lift assistance is an ESP system, normally implemented when a well is worked over and recompleted. Placing an in-well ESP artificial-lift system within the primary completion enhances production during the well-pressure- depletion period, preventing the need of at least one workover to install the ESP and preventing deferred production while waiting for a capable rig to perform the workover. In 2009, considerations for in-well lift completions moved forward with conceptual development of a dual canned ESP system in collaboration with an operator. Although dual ESPs have been run before, the use of a dual canned ESP system in the Lower Wilcox requires a significant number of additional completion components that require additional control lines for their operation.