LEIDEN, the Netherlands – Heerema’s semisubmersible crane vessel Thialf has removed Shell U.K. Ltd.’s Goldeneye wellhead platform in the central North Sea.
The Thialf removed the 1,280-metric ton (1,411-ton) topsides in one lift. It was then transferred to the vessel’s deck for transportation.
The jacket involved cutting skirt piles using Deco Subsea’s internal abrasive water jet cutting techniques at -3 m (-10 ft) below the seabed. After which, the 3,019-metric ton (3,328-ton) jacket was removed and remained suspended in the Thialf’s cranes for transport to Vats, Norway.
The platform has been set down at the AF Environmental Base yard in Vats, Norway, to be dismantled for reuse and recycling. It is anticipated that more than 97% of the material will be recycled.
In 2003, the Thialf installed the Goldeneye platform about 100 km (74.6 mi) northeast of the Aberdeenshire coast in 120 m (393 ft) of water. It included five platform wells with a direct tieback via the Goldeneye pipeline to the St. Fergus onshore facility. The Goldeneye gas field started production in 2004. Cessation of production was granted in 2011.
According to Heerema, the Thialf will now undergo yard maintenance, including modifications to the vessel’s A-Frame. This is expected to enable the Thialf to expand its service area and deliver solutions in the Baltic and the Black Sea regions.