Decommissioning

ATCE Highlights: Boosting Recovery From Maturing Fields and Decommissioning

The 2014 SPE Annual Technical Conference and Exhibition (ATCE) in Amsterdam drew people from all over the world, covered global themes, and focused on the triumphs, challenges, and remaining opportunities for the North Sea.

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UK Forties Alpha Field facilities
Courtesy of Apache Corporation

I have just returned from the 2014 SPE Annual Technical Conference and Exhibition (ATCE) in Amsterdam, which was well run, well attended, and chock-full of interesting information for facilities engineers. In Europe for only the second time in SPE’s history, the conference drew people from all over the world, covered global themes, and focused on the triumphs, challenges, and remaining opportunities for the North Sea.

The North Sea perspective was of most interest to me, because it had been more than 25 years since I last worked there. Then, there was a number of huge producing fields such as the Forties, Brent, Ninian, Statfjord, and Ekofisk. A production minimum of 300,000 BOPD was the norm for these fields (and much higher in some cases). Today, the situation is slightly different. A special session at the ATCE centered on the Forties and Ekofisk fields and how they are experiencing a new lease on life.

Robert Davenport of Apache North Sea described the factors that have enabled an increase of at least 100 million bbl of recoverable oil in the Forties field. An effective asset management, new technology, and targeted investments in wells and facilities were all critical to this success. However, the most important factor to me was how Apache accomplished this result: It used a management strategy that emphasized determination, a sense of urgency in all decisions, and a laserlike focus on growth with efficiency.

It is no accident that Apache accomplished best-in-peer-group growth, while improving production efficiency and delivering lower-than-average operating costs. This achievement demonstrated how excellence in engineering plus an enabling management philosophy equals success. The Forties story is clear evidence that the old adage is true: the best place to find oil is in an oil field.

John Hand of ConocoPhillips delivered an equally inspiring message when he reviewed Ekofisk, a field with a production life of 80 years. Ekofisk has been in production since 1971 and targets a recovery factor of more than 50%, up from an original recovery of 17%. The field has the problems of a maturing asset that has undergone waterflooding (water management, aging infrastructure, and facilities bottlenecks), but also has the unique and well-known issues of subsidence and compaction. In essence, the company is faced with sinking facilities structures, as well as wellbore buckling/collapse, and changes in reservoir permeability.

ConocoPhillips instigated a truly integrated approach to field management, which included improved collaboration internally and with its service providers. Additionally, new infrastructure investments (e.g., wells, platforms, and subsea tiebacks), existing infrastructure upgrades (e.g., jacking up/elevating platforms), and adoption of advanced seismic and reservoir modeling practices ensured optimum recovery and effective crude handling and water management.

As a result, higher production efficiencies were delivered by more effective wells and processing facilities. Again, this is a success story based on good engineering and a management philosophy that fostered creativity and cross-functional solutions.

The Forties and Ekofisk are examples of fully understanding your business and delivering simple and effective solutions. Solution is the key word. Neither asset used only technology, only well/facilities investments, or only decision and risk modeling. A complete asset solution was required. In both cases, there was no room for the superfluous or added complexity. The purpose was to just find the solution and execute with excellence.

As many of us will attest to, this is not easy: Simplicity is not easily attained, but when we get it right, we can achieve extraordinary results. An 80-year field life and industry-leading asset performance illustrate this feat at Ekofisk and Forties.

In www.onepetro.org, several articles under the “aging facilities” umbrella identify a number of common factors that need to be addressed in considering field life extension. Among the more obvious are fitness for duty (will my old facilities work under new demand?), obsolescence (can I still buy spares?) and legislative changes (have “legs and regs” changed over time and can I meet the new challenges?).

Success factors that are perhaps less obvious are workforce competencies (do we have the skills to operate differently?) and asset management systems (will my old way of doing business work in the new era?). As the Forties and Ekofisk fields have shown, we need facilities and management systems optimized together and working in harmony to deliver outstanding results.

Even if life extension is a successful period of a field’s life, eventually, we will come to the phase of asset retirement and the task of decommissioning. At the ATCE’s annual PFC dinner, a full house listened to experts discuss the related technical, commercial, and legislative issues. It was obvious to me that the North Sea faces many challenges in this space, not least of which is cost.

One estimate is that in the UK sector alone, more than USD 23 billion will be spent on decommissioning in the next 10 years. One of my takeaways from this session was the concept of designing for decommissioning, a philosophy aligned with life cycle design (see “Engineering for Decommissioning” in the August Oil and Gas Facilities issue). The attributes for effective decommissioning are “baked” into facilities designs, just as changing water cut and lower reservoir pressure are accounted for today.

We do some of this right now, but the session’s expert panel agreed that there is much more value in this space and we need to do a better job as an industry in the future. Also, we need to be more proactive in determining the stage in a field’s life when we should actively start managing assets for decommissioning. The consensus was the earlier the better. This session generated a lot of interest, and is further described on page 30.

Lastly, the cover story in the November JPT is about aging asset removal, a sister topic to field life extension and decommissioning. SPE’s focus on mature and aging assets is not coincidental. It is a PFC hot topic and one championed by the PFC technical director, Howard Duhon.

As a discipline, we have finally realized that the end of a field’s life is just as important as the beginning, and that as facilities engineers, we have the requirement to be skillful and successful at both stages.