Operational Procedure for permanent P&A of Subsea Wells
MetadataShow full item record
All oil-and gas wells ever drilled on the Norwegian continental Shelf will be abandoned at some point. The operating companies are entitled ensure no leaking to the surface from the reservoir in an eternal perspective according to Norwegian regulations. This requires an extensive planning and is potentially a costly affair. A hunger for finding alternative methods, equipment and barrier materials to simplify the permanent P&A operation is central in the planning of abandonment. With today s Brent crude oil price many companies focus on minimizing cost through better planning and new procedure and technology. Since every well will be either temporary or permanent abandoned at some point, lot of money can be saved on thorough planning and through re-thinking of the abandonment operation. A new structure has been developed to simplify the P&A planning. This structure divides the abandoning operation in distinctive phases, in which after each phase the well can be considered as temporary abandoned and one step closer to permanent abandonment. For smaller companies operating at Norwegian continental shelf, perhaps struggling with the liquidity, the phase classification can be revolutionary. The company will have the opportunity to spread the cost since the P&A operation can be done over a longer time perspective by taking one phase at the time. There is a potential in implementing new technologies or barrier material to make the P&A operation easier. This requires the operating company willingness to invest in these solutions together with service companies. This thesis presents a P&A procedure suggestion of two subsea production wells, operated by Det norske, based on today s technology and methods. It was desirable from Det norske that the author of this thesis would try to come up with new solutions, feasible or not, to get a new point of view for further discussion the day these wells will be planned for abandoning. Based on the well categorization, new approaches, contingency plans and implementations of new barrier materials and technologies it is discussed if the P&A operations of these wells could more cost efficient through rig less solutions or time efficiency.