Italian major Eni is in the process of buying Saipem’s Firenze Floating Production, Storage and Offloading (FPSO) vessel located on its deepwater Aquila field in the Adriatic Sea offshore Italy.

The FPSO, which replaced the field’s original floating production unit in late 2011, is to be bought along with its related assets for US $463.32 million, according to fellow Italian Saipem. It is not yet clear what Eni intends to do with the FPSO in terms of the field’s continued operation, or whether it has other plans.

Saipem said only that “with reference to the sale of the Firenze FPSO business line to Eni, following the approval of the transaction by Eni’s Board of Directors, Saipem confirms that the signature of the contract between the two companies is scheduled for 13 December 2013”.

Saipem is split into two Business Units – Engineering & Construction, and Drilling – with a major focus on remote areas and deepwater.

The original FPSO on Aquila, which sits in 815 m (2,674 ft) of water, was a ground-breaking deepwater development of its time, developed in 1998 and located 50 km northeast of Brindisi. At the time of its installation it became the second deepest moored FPSO ever installed.

In 2006 the original FPSO was deemed unfit for further use, with a second development phase then implemented by Eni using a converted Afromax tanker. The plan included mooring the replacement FPSO using the existing Firenze FPSO mooring legs.

Eni wholly owns and operates the field, which was discovered in 1981 but remained undeveloped until the mid-1990s when enough reserves were proved up to improve its economics and produce it via two production wells. FMC Technology was contracted by Eni to design a subsea solution that eliminated the need for workovers. The subsea tree configuration included six annulus lift and downhole penetrations; four support flat packs containing one electric and one hydraulic line each. A hydraulic line was provided for operating the subsurface safety valve, and a separate chemical injection line for asphaltene anti-deposition treatment was also provided.

The two subsea wells were then connected to six risers and three umbilicals via a 6-inch-diameter production riser, a 2-1/2-inch-diameter gas lift riser and a multiplexed electrohydraulic control umbilical, then tied-back to the FPSO.

The second phase of development involving the replacement FPSO got under way in 2009 to increase the field’s productivity and life expectancy, with a contract awarded to Saipem for the supply and operation of the FPSO. The floater has a storage capacity of 700,000 bbl and a production capacity of 12,000 b/d of oil.

There are several significant prospects in the vicinity of Aquila, including the Cygnus prospect, in the adjacent licence operated by Northern Petroleum. Cygnus is estimated to have an unrisked prospective resource of up to 790 MMbbl of recoverable oil. The prospect is adjacent to and up-dip of the Aquila field.

Offshore