Worlds' largest ship lifts Shell oil rig Brent Delta platform

The largest vessel in the orld successfully lifted, a 24,000-tonne oil rig platform from the North Sea, in what is the first instance of an operation of its kind.

The mammoth engineering task formed part of the first phase of decommissioning of one of the most important oilfields in the region.

The ship, Pioneering Spirit, earlier called Pieter Schelte, is the world's largest ship. It is designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipeline.

Designed entirely in-house by Swiss-based Allseas Group, the 382 metres long, 124 metres wide vessel was built in South Korea by Daewoo Shipbuilding & Marine Engineering  and was completed in 2014.

The positioning of the specially-built £2.4-billion Pioneering Spirit, around the Brent Delta platform took hours.

But the powerful hydraulic system lifted the topside off its supporting legs, and set a world record in the process.

The topside was now fastened to the 382m-long ship for transport to a scrapping yard near Hartlepool.

The project will last 10 years, will see the firm remove all four oil platforms from the Brent field in the North Sea located 115 miles northeast of the Shetlands.

The Brent field, one of the largest fields in the North Sea accounted for 10 per cent of total North Sea production during the past four decades.
When running at peak production the four rigs would pump 500,000 barrels of oil out of 154 seabed wells every day.

According to commentators, decommissioning the field will be a major infrastructure project. The operation was under close watch of the industry as it was the biggest North Sea field to be dismantled so far, with hundreds more to follow.

Brent Delta was among the first platforms to be built in the very early days of the UK's oil and gas industry.

It was located 115 miles (185km) north-east of Shetland in a cluster of four platforms which made up the Brent field.

Being among the first, it was now at the end of its life and had to be removed.

Brent Delta was the first major piece of infrastructure to be decommissioned in the North Sea. Over the next decade, more than 100 platforms would be completely or partially removed in the waters of the UK and Norway.