Chevron in Captain rethink
Friday 24 June 2016
However, Chevron confirmed this week that work will now focus — initially, at least — on a brownfield expansion centered on the existing Captain platforms, located in a segment of the field housing the existing platforms, known as Area A.
Chevron expects the initial expansion phase to include at least six long reach horizontal injection wells drilled in Area A, with the first one to be drilled in early 2017.
This initial brownfield expansion will include bulk provision of chemicals and facilities modification on the existing Captain wellhead protector platform, the installation of new polymer mixing equipment to expand processing capacity that will tie-in to the pre-existing injection system, and polymer storage facilities.
Chevron, however, still appears intent this brownfield first phase will be followed later by a full-field EOR expansion once market conditions improve.
“Chevron North Sea, operator of the Captain field joint venture, has determined the best opportunity for successfully developing Captain EOR is in stages, with the first phase a significant brownfield expansion in the platform area of the field (Area A), starting in 2017,” a spokesman said.
The spokesman said the staged approach will allow the project to “proceed with meaningful development in the near term, whilst benefiting from critical polymer technology learnings until the economic environment improves”.
He added Chevron was committed to moving forward with polymer EOR at Captain with its partners and the Oil & Gas Authority (OGA).
Chevron has now notified its four bidders it is halting the EPC process for the BLP — comprising a 7600-tonne deck, a 6000-tonne jacket, a 400-tonne bridge plus thousands of tonnes of piles. Contractors have also been told about the change of approach for the development.
The spokesman said: “As the initial brownfield expansion scope will not require a BLP structure we have notified shortlisted companies that the current EPC bid process will be discontinued. We will retain the capacity to resume FEED work on a full-field deployment.”
Chevron has so far not revealed the identity of those companies. However, Upstream reported previously they are Heerema Fabrication Group, Rosetti Marino, Dragados Offshore and UK defense contractor Babcock.
Chevron previously intended to take a final investment decision this year on the full-field Captain expansion but said in February that was longer on the agenda as it looked to mature the engineering in order to improve the project value and decrease commercial and execution risk, including further evaluation work on the polymer injection solution.
Around the same time, Chevron is understood to have asked FEED contractor Amec Foster Wheeler to carry out brownfield studies to see if Captain’s existing facilities could be modified to support the needs of the EOR scheme, instead of building a new bridge-linked platform.
Chevron has been carrying out pilot studies for several years to test the injection of polymerised water into the reservoir to increase output and extend field life.
Sources familiar with the project told Upstream previously that the polymer used in the injection “definitely works” but that Chevron needed more time to “fine tune” the exact mix of polymer and carrier fluid.
The Captain field is located in Block 13/22a about 145 kilometers north-east of Aberdeen, in the Outer Moray Firth.
The field currently includes a wellhead protector platform and BLP connected to a floating production, storage and offloading vessel and two subsea manifolds tied back and connected to the platforms by a suite of pipelines.
In 2014, net daily production averaged 18,000 barrels of liquids and 3 million cubic feet of natural gas.
In December 2014, Captain EOR moved into FEED. The selected — and now postponed — concept is a fixed platform bridge-linked to the existing Captain facilities, combined with an extensive injection well drilling campaign.
Captain is operated by Chevron with 85% and Dana Petroleum on 15%.