The Bonga North West field is located in the oil mining lease (OML) 118, at a depth of more than 1,000m, approximately 120km off the Nigerian coast. The brownfield development will enhance production at the existing Bonga facility.
The field is operated by Shell Nigeria Exploration and Production Company (SNEPCo), which holds a 55% stake in the field. Other partners in the field are Esso Exploration & Production Nigeria (Deepwater) (20%), Total E&P Nigeria (12.5%) and Nigerian Agip Exploration (12.5%) under a production sharing contract with the Nigerian National Petroleum Corporation.
Production from the first well at the field commenced in August 2014, while the remaining wells came on stream by January 2015.
Bonga North West field development details
The field has been developed as a subsea tie-back to the Bonga main field using the existing subsea infrastructure. It has also minimised its environmental impact by utilising the available infrastructure.
The development encompassed the drilling of six wells, including four oil-producers and two water injectors, at the deep-water field.
A new undersea pipeline connects the wells to the Bonga FPSO export facility. Oil is processed and loaded into tankers and shipped for marketing purposes.
The development also involved a network of new production manifolds, subsea umbilical systems, oil production and water injection flowlines and subsea tree systems. Subsea infrastructure was installed 1,000m below the surface on the seabed.
The development was carried out by remotely controlled robots below the surface to connect new and existing equipment. Additional pipes from the well were also connected by the robots.
Bonga FPSO details
The existing Bonga FPSO has been upgraded to accommodate the additional oil flow from the new field. At its peak production, Bonga North West produces 40,000boe a day.
Chemical injection systems were incorporated in the FPSO to prevent the new pipes from corroding or freezing.
The 300m-long FPSO processes oil onboard, stores it and then transports it to a single-point mooring buoy anchored nearby. It is then supplied to markets for export by tankers. The Bonga North West field development ensures that production from one of the world’s biggest FPSO is not disrupted.
The Bonga main field is Nigeria’s first deepwater project and started producing in 2005. The field lies in water depths of 1,000m and covers an area of 60km².
The project helped to increase the country’s oil capacity by 10% and has a production capacity of approximately 200,000boe a day and 150mmscfd of gas a day.
The Nigeria Liquefied Natural Gas Company (NLNG) located at Bonny Island receives gas from the Bonga development from where it is exported to European and global markets as LNG.
Contractors involved with Bonga North West project
An engineering, procurement and construction (EPC) contract for the project was awarded to FMC Technologies. The scope of work included the installation of trees, low riser adapter spool, manifolds, well jumpers and other subsea equipment.
Aveon Offshore was contracted by FMC Technologies in a $30m contract to fabricate components for the subsea production system.
Weltek was awarded an engineering, procurement, installation and construction (EPIC) contract for the topside facilities, as well as four methanol injection and four corrosion inhibition pumps, including skids and accessories, electrical switch gears and control buildings.
A $200m contract was awarded to Saipem for the subsea project. Contracts were also awarded to Aker Solutions and Invensys/Sidler.