OSLO, Norway — The Norwegian Petroleum Safety Authority (PSA) has commissioned Reflekt to review current knowledge on bismuth alloy applications for permanent P&A operations offshore Norway.
The aims include determining where the industry is heading in terms of development, testing and use of bismuth alloy as a well barrier material for offshore wells. Reflekt will not provide opinions on the different technologies and the suitability of bismuth alloy as a well barrier material.
The PSA’s regulations concerning securing of wells (Activity Regulations 88) include an assurance that there will be no leakage of hydrocarbon to the environment after the well has been abandoned.
One technology under development is the use of bismuth alloys as a well barrier material. These can be deployed via wireline/electric line and therefore without the use of a drilling rig.
An unnamed operator on the Norwegian Continental Shelf has qualified and used bismuth alloy as a well barrier material in wells with low differential pressure and low ambient temperature, the PSA added.
Those contributing input to the report are Aker BP, Total Energies, BiSn, Interwell, ISOL8 and Wellstrøm. SWIPA (Subsurface Well Integrity and Plug & Abandonment), a consortium of SINTEF, NORCE, NTNU, IFE and UiS has also participated.