Project Profile
Value: Undisclosed
Location: Northern Timor Sea, with Laminaria 12km to the north-west, Australia
Start-up Year: 2000
Oil reserves: 20 million barrels
Water depth: 27m-30m
Buffalo field produces in excess of its 40,000bpd design capacity. Since 2000, the field had an uptime of 98%. The field came into production 15 months after project sanction. Buffalo is located in the northern Timor Sea, with Laminaria 12km to the north-west and Elang around 55km to the south-east. The Buffalo reservoir lies under the shallow water Big Bank – measuring 12km in length and about 3km in width. This is flat, with a water depth ranging from 27m-30m, while its edges drop off nearly vertically to approximately 330m. The field is operated by BHP Petroleum (50%), on behalf of Canadian Petroleum (50%) The Buffalo field was discovered in October 1996, when BHPP tested the Buffalo 1 well. The well flowed at 12,000bpd of light 53d° API oil. The oil has a particularly low GOR of 120. The field has probable reserves in excess of 20 million barrels. Gross production is expected to peak at 40,000bpd over a three year field life. The BHP share of proven and probable reserves is around ten million barrels.The Buffalo Venture has a length of 288m, a beam of 39m and a draught of 15m. Sofec was responsible for the provision of single-point mooring. In turn, it subcontracted the swivel to Framo of Norway. Modec also subcontracted the design and project management of the process modules to Schlumberger, in Singapore. The process modules were built by Hup Seng Engineering.
WELLHEAD PLATFORM (WHP)
This was designed by Worley Engineering and built by ASC-Engineering, of Adelaide. The five-wellhead unmanned steel platform is located on Big Bank. It produces crude oil (plus some associated gas and water) from two development wells. The WHP is remotely controlled from the FPSO, via an umbilical. Oil, gas and water flow to the permanently moored Buffalo Venture, via rigid steel flowlines and flexible catenary risers. The 330t platform was towed from Adelaide in an upright position to the field, where it was installed by the Reading and Bates jack-up rig, Ron Tappmeyer.
INSTALLATION
ICON Engineering installed the wellhead platform. The structure was loaded out and transported in a 21-day tow, from Adelaide, in the vertical position. At Darwin, the mooring and installation equipment was added prior to departure for the field. ICON also carried out the hookup and commissioning. The Buffalo project used rigid steel flowlines in a pliant wave configuration (provided by Coflexip Stena Offshore). This included distributed buoyancy and it was tethered to the seabed by two gravity bases per riser.
MOORING
Two anchors sit in water less than 30m deep, while the other four sit at a depth of over 300m. The shallow/deep single-point mooring (SPM) was designed by Sofec, in Houston. Sofec contracted Malaysian Shipyard & Engineering to build the mooring.
Operators:
Carnarvon Petroleum Ltd: Operator with 100% interest
Contractors:
Sofec: Build the mooring
Hup Seng Engineering: Build the process modules
ICON Engineering: Hookup and commissioning
Coflexip Stena Offshore: Supplied flow-lines in a pliant wave configuration
Modec: Design and project management of the process modules
Subcontractors:
Malaysian Shipyard & Engineering: Build the mooring
Framo: Provided the swivel
Schlumberger: Design and project management of the process modules contracted by Modec