Case History Of A 5 Zone Multi-Drop Hydraulic Control Intelligent Offshore Completion In Brunei
Authors: Skilbrei O. , Chia R. , Schrader K. , Purkis D. 
Published: October 2008

Description of the Proposed Paper

Describe the background and history of a producing well leading up to a workover decision and installation of a multi-zone intelligent well completion system. State the guidelines used to design and complete an offshore horizontal five zone well with intelligent completion equipment. State the success and/or problems seen during the installation. Highlight the lessons learned during design and installation and show benefits of such a completion during the production life of the well.

Application:

Offshore completions in development wells targeting multiple stratigraphic units located over highly compartmentalized fault blocks with distinctly separate fluid contacts and pressure regimes. Control of water breakthrough and GOR management on multi-zone oil producers. Safe completion of complex horizontal wells.

Results, Observations, and Conclusions:

Installation was done successfully and safely. The defined completion successfully worked as designed.

Significance of Subject Matter:

The use of multi-zone intelligent completion equipment to optimize the reservoirs is critical to the economic success of this type of field. The technology used provided the capability to produce each zone alone or commingle production without subsequent well intervention to shut-off zones after water breakthrough or high GOR production. These capabilities will be shown to improve the overall reservoir recovery.

Introduction

The oil and gas industry is the primary contributor to Brunei's economy. The exploration and production of Brunei's hydrocarbon reserves is undertaken with great care to extend the income from this natural asset for future generations. To this effect, Brunei Shell Petroleum (BSP) is an early adopter of new technology in this region, to solve technical challenges and improve economics and reserve recovery. Examples of this include the use of innovative directional drilling technology1, the integration of intelligent completion equipment with expandable sand control technology2 and use of solid expandable tubulars3.

A high level of local experience in Brunei contributes to the development of the Iron Duke field and neighbouring field such as Ampa and Champion. The Iron Duke field is located offshore, 50 km from the Brunei coast. Iron Duke came online in 1992 with reserves estimated at 17 million m3 of oil (105 MMbbl) and 27 billion m3 of gas (950 bcf) in the Upper Miocene shallow marine sandstones. Current production from 7 producers is 3000 m3/day liquids and 2.5 million m3/day gas. In the Iron Duke area, 25 wells have been drilled during a major development drilling campaign.

The Iron Duke structure is an anticlinal dome dissected by a large number of collapse faults. A long strike of the collapse fault structure, the phenomena of "fault flipping" is observed. The faults are often sealing and define a large number of blocks within the field. Vertical sealing capacity may vary due to the sand shale sequence.

The drive mechanism in Iron Duke is predominately gas cap expansion with limited aquifer support; thus wells are targeted close to the oil water contact (OWC) to delay gas breakthrough. Well ID-19 is one of several development wells targeting five main strategraphic units located over several fault blocks as shown in Figure 1.