Intelligent energy in action

The PSVM project subsea layout. Images from BP.

BP’s Field of the Future program has been put into action on the PSVM development offshore Angola. Elaine Maslin reports.

BP’s deepwater PVSM project offshore Angola is an example of intelligent energy in action, said BP region president, Angola, Martyn Morris.

The project, standing for the Plutão, Saturno, Vénus, and Marte fields, came on stream last year, about 400km north west of Luanda in 2000m water depth. The subsea infrastructure is one of the largest layouts in the industry in deep water, at 38km x 18km-wide and comprising 77,000-tonne of seafloor hardware. At least 40 production, gas and water injection wells will eventually be connected to the FPSO through 15 subsea manifolds and associated subsea equipment.

When BP was working on the development, it decided to make an example of it, using new technology where it could, drawing on BP Field of the Future pro- gram, launched in 2001, Morris said. BP describes Field of the Future as harness- ing the opportunities created by the latest digital techniques to deliver benefits in operating efficiency and recovery.

The program itself is underpinned by the linking of BP’s operations in Angola to 35 Advanced Collaborative Environments (ACEs) worldwide, accessing real-time data about its reservoirs and operations. Currently the data comes from offshore, through satellite links, although BP is looking towards a fiber optic solution.

“As part of the Field of the Future pro- gram, we put all the bells and whistles into the PSVM facility,” Morris told the SPE Intelligent Energy Conference in Utrecht in April. “We decided to put in as much of this technology as we could. It is about putting in equipment to calculate real-time data. We talk about the field of the future, but this is the field of the future, today.”

BP's PSVM FPSO. Image from BP.

The technology

A key concept on the field has been enabling information from technologies used to be connected back to offices in Luanda, where it is then fed into an the ACE, which links the onshore team, offshore team, and any other offices required, such as Houston or Sunbury (UK), into the working environment. By doing so, BP can draw on its global experts to manage anything from drilling to subsea sand detection, and flow control.

Feeding into the ACE is information from an array of technologies. Remotely operated vehicles are used to fly along flowlines, collect subsea samples, and position subsea acoustic monitors, to monitor wells.

“Every single well we have has a multiphase flow meter,” Morris said. “This helps calibrate the integrated surveil- lance information system, which allows us to calibrate and check all the dynamic data we are bringing in.”

Downhole flow control is used for water injection management, and tracers are used on most water injection wells and three gas injection wells. Subsea sand detectors for integrity management and an integrated subsurface information system has been deployed with alerts, rate and phase, well test, and ARPE modules. A subsea acoustic monitoring system was used to carry out interference testing.

4D seismic will also be deployed on PVSM. BP will carry out its first time lapse survey in 2014, 18 months after production started in December 2012. Using specialist vessels, it will shoot new surveys every 18-months to two years

and use its own proprietary software to analyze the data. Data collected will be combined with production logging tools to track water movement through the reservoir, and to see where oil remains. This will help increase recovery 16-18% by identifying opportunities and drilling new wells, Morris said.

Slugging

One of the biggest risks on PSVM was during start up, specifically around slugging. A slug controller was developed, which provided significant benefit on start-up for the Saturno field, which sits some 15km from the Plutonio, at the center of the development.

The slug controller’s role was to stop production oil and gas backing on itself in the 12in. riser, which travels up through the 2000m water depth. A riser with oil and gas can get unstable. The slug controller uses algorithms, based on pressure, temperature, and flow data, to work out the volume of oil, based on weight, in the riser, and actuates the inlet valve (riser top control valve) accordingly, so there are not huge variations in inlet pressure.

“If you have a slug coming up the riser, it is important you do not let the fluid in too quickly,” Morris said. “It can cause vibration at the bottom of the riser and huge fluctuations in pressure and you can end up tripping the plant on high pressure trips.”

The technology was developed with Cranfield University in the UK before being trialed on the Valhal field, off Norway.

“Without this we would not have been able to start up the Saturno field, due to the distance of the field from the FPSO and the depth and topography of the seabed,” Morris said.

Start of a digital era

During field startup at the end of 2012, using the ACE, staff from Sunbury, Houston, Angola, and the offshore team were brought together 24-hours/d for the first week, bringing in experts who would not have been able to be on location and would still be available to other teams. Production ramped up to 75,000boe/d without much problem, Morris said.

“The digital oilfield is here,” he said. “Real-time data is available, and there is lots of it. The trick is knowing what to analyze, what to use, and when to take action.”

“There is some more work to be done,” he told OE. “My feeling is that the next step-change will be having machines doing basic analysis, advising you where issues are potentially arising or have arisen, then you take action. The more instrumentation you have, the more maintenance it requires, and it can break and go wrong, and, if you are not looking, you might miss something. We have to help ourselves get smarter; it’s business transformation. You have to have your organization working in a way that you can use the data and that requires leadership—the executive team, the COO—to be enlightened by the technical team.”

The future

Nineteen discoveries in Block 31 have been announced to date. Future development is expected to be comprised of multiple hubs similar to the first development (PSVM). The second development for the southeast area of Block 31 is in the planning phase.