The Bonga North West Project (BNW) is the first subsea extension to the existing Bonga Main subsea facility, as well as the first major subsea tie-back to be executed in the Nigerian sector of the Gulf of Guinea deepwater. This paper provides a detailed discussion of the process of integrating the new systems comprising subsea producers, injectors and all the ancillary facilities, to an existing, but different, Original Equipment Manufacturer (OEM) system. It will also give a detailed explanation of the intermediate systems engineered to achieve this integration, and the process used for successful integration of the two different systems. The planning and deployment of a new Completions Management System for the commissioning of the new facilities, and the strategy adopted to achieve a flawless start up will also be presented in this paper.
To ensure a flawless start-up, Shell Project standards were employed. A Simultaneous Operation (SIMOPS) emergency shutdown was carried out to check the integration of the new subsea infrastructure as part of final checks performed prior to start up.
To enable seamless integration between the two different subsea systems, staged system integration and verification tests were planned and executed to ensure that each component performs as per intended design. A series of assurance activities were carried out to demonstrate alignment between design intent and healthy operations of the new subsea system, for the following:
Correlation of field data with design analysis for both the existing and new systems
Benchmarking the performance of the new integrated system against the old system
Topside and Subsea controls integration between two distinct systems
Environmental barrier and isolation assurance
The success of this endeavor is evidenced on a Flawless Start-Up and operation of the new system as an integral part of the nine-year onstream Bonga Main system. Disruption to production and impact to the existing asset were successfully minimized.
Significant insights and learning were gained in the areas of subsea communication and control interfaces, defining multiple interfaces, integrated system testing, flawless startup and sharing of information across multiple vendors.
