World record set after large oil rig lifted and shipped in one piece

19th May 2017 By: Donna Slater - Features Deputy Editor and Chief Photographer

World record set after large oil rig lifted and shipped in one piece

BRENT DELTA The large and ageing oil rig arrives at the Able Seaton Port to be recycled

North Sea oil rig the Brent Delta platform, belonging to oil company Shell UK, was recently successfully lifted off its three-legged structure in the Brent oilfield, about 180 km off the coast of the Shetland Islands, setting a world record for the heaviest single-piece lift at sea.

The 24 000 t oil rig is being decommissioned and is set to be recycled on a land-based facility – Able Seaton Port, in Teesside, north-east England, in the UK.

The world’s largest construction vehicle ever built – offshore pipelay and undersea construction company Allseas’ Pioneering Spirit – conducted the lift and sea ferry to the port.

The twin-hulled vessel is 382 m long and 124 m wide, with a 122-m-long and 59-m-wide slot at the bow that enables Pioneering Spirit to straddle a platform and remove entire topsides of up to 48 000 t in a single lift using eight sets of horizontal lifting beams.

Able Seaton Port founder and executive chairperson Peter Stephenson says that, at the port, the Brent Delta will be prepared for a decommissioning process, in which at least 97% of the structure is expected to be recycled. After arriving, the topside was transferred to a 200-m-long barge, the Iron Lady, which was successfully moored at the port’s specialist facility on May 2.

“Today is a triumph for everyone involved in one of the heaviest lifts ever to take place, especially our partners, Shell and Allseas, with which we have worked for several years to meet the huge technical challenges involved,” said Stephenson at the arrival of the rig at Able Seaton Port on May 2.

The topside will be skidded onto the new multimillion-pound ASP Quay Six, one of the strongest in Europe, for the start of the decommissioning.

Stephenson says that the choice to use Able Seaton Port was the “clearest possible vindication” of the company’s determination to establish the port as a “world-class facility”, adding that the Brent Delta decommissioning project was the most significant project of its type to date and of “crucial importance” to the port, as it was selected among an initial list of 131 potential disposal yards.
He explains that upgrading the port to handle such a large project involved a significant commitment from the port, with an investment of £28-million in a new quay and associated developments. “We believe that the investment is worthwhile, not only for this contract but also for the potential for us to be at the forefront of a business that is set to grow to meet the need to decommission platforms as they come to the end of their operational lives.”
The next stage entails the transfer of the Brent Delta to the new Quay Six, after which Able Seaton Port will conduct detailed surveys in preparation for the decommissioning programme, which is expected to be completed within 12 months.