The world’s largest offshore construction ship has delivered the 8,500-tonne Ninian Northern platform jacket for decommissioning in Shetland.
It is the second visit to Lerwick by Pioneering Spirit, owned by Swiss-based offshore contractor Allseas Group, but the first time she has operated at quayside in a UK port.
On her arrival from the North Sea, the giant vessel went straight to the port authority’s Dales Voe base to lift steel structures onto a barge for removal.
In a complex operation, the huge 1,253ft-long, 407ft-wide vessel then manoeuvred to transfer the 272ft-high jacket via a barge — Allseas’ Iron Lady — for loading-in to a heavy-duty decommissioning “pad”.
Pioneering Sprit’s latest project in Lerwick follows her first visit to the Shetland port, in 2020, to deliver the Ninian Northern topside.
Lerwick Port Authority chief executive Calum Grains said: “The second successful visit by Pioneering Spirit highlights another example of the deep-water harbour’s capacity and facilities to handle large vessels and major projects for energy industries, and points the way to future operations.”
The jacket is being decommissioned under a joint venture between waste, water and energy management services firm Veolia and logistics company Peterson. The same two international firms processed the topside.
Ninian Northern was installed in 1978 and put into production two years later, before finally ceasing output in 2017.
Canadian Natural Resources took over operatorship of the Ninian and Murchison fields, both in the northern North Sea from US company Kerr-McGee in late 2002.
It was the Canadian company’s debut North Sea deal.
A draft decommissioning programme for Ninian Northern – one of three platforms on the Ninian field, about 240 miles north-east of Aberdeen – was submitted to the UK Government in early 2017.
Calgary-based CNR permanently ceased production from Murchison, whose jacket and topsides were among the largest in the UK North Sea, in 2014.
Demolition and recycling work on the largest structures of the Murchison platform were carried out at a decommissioning facility in Norway.