ENERGY DECOMMISSIONING
CASE STUDY
Veolia Repsol – recycle Buchan Alpha production rig
Project:
To safely deconstruct and recycle the remains of the Buchan Alpha production rig.
The rig was towed from its North sea location to Dales Voe three years ago and was partially demolished at the Dales Voe Quay. Severe weather and storms hampered the works and a particularly strong storm caused the rig to break free and drift from its moorings across the water and ground in shallow water in a remote location. The dismantling of Buchan Alpha was therefore a challenging project.
Ocean Kinetics were awarded the contract to remove and recycle the remaining 3,500 tonnes of the rig in July 2020.
Solution:
The initial stages of the project involved thorough surveying, planning, and modelling the lifting of the rig and its elements. Preparing the rig for demolition while still maintaining the structural integrity was a complex process. Excess steel was thereby removed, and the pontoons underwent underwater repairs to allow them to be re-floated and towed to Lerwick Harbour.
16 number 300 tonne SWL lifting points were welded and tested to allow the safe removal and placement of all pontoons using the large sheerleg Hebo-9 with a capacity of 800-tonnes. Each pontoon was lifted onto the Green Head Base decommissioning pad, with the heaviest pontoon weighing 760 tonnes.
After an arduous period of day and night shifts with more than 15,000 hours worked from our skilled design and marine crew, the Buchan Alpha was completely dismantled safely without any incidents or injuries. The steel is now all contained within the decommissioning pad at the Greenhead Base ready for recycling by sub-contractor, John Lawrie, and Dales Voe has now returned to its natural landscape.
KEY FACTS
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For assistance and support please contact:
John Henderson
john.henderson@oceankinetics.com
T: 01595 697 907 / 0780 121 5627
