The M-I SWACO Production Technology group won the prestigious International Platinum Award at the Energy Institute Awards held in London for its innovative technology, developed to safely extract oil trapped in the attic space of the subsea storage cells in the Dunlin oilfield.
A world’s first and the result of three years of intensive work, the Shell
Dunlin Attic Oil Recovery project was unprecedented in its scale and complexity
in the North Sea. It involved in-situ gas generation within the cell structure
of the North Sea installation. The aim of the project was to safely free the
four cell groups of the remaining 1.5 million barrels of liquids, including
250,000 barrels of oil.
The patented technology displaces the crude oil layer to the level of the
export pipe for recovery. Following complete oil recovery, the gas cap is
absorbed using a scavenging system to fill the cells with seawater. The 76
supporting cells, located on the seabed 495 feet beneath the Dunlin platform,
now are full of seawater and free of oil.
Throughout the process, the risk of failure to deliver the technology was
managed through close cooperation across the multi-disciplined team of major
exploration and energy firms.