Making the 'Subsea Factory' a Reality

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Rigzone talks to GE Oil & Gas about its plans to develop subsea equipment that will ultimately be used in the "Subsea Factory" envisaged by Statoil.

 

In 2012, Statoil ASA came up with the concept of the “subsea factory” as one of a number of technological strategies designed to help it achieve a production target of 2.5 million barrels of oil per day (MMboepd) by 2020.

Recent announcements from the Norwegian oil and gas major regarding capital spending suggest that its 2.5 MMboepd target could be missed, but the plan to develop a subsea factory system still remains.

At the moment, subsea production systems exist that involve wells located on the seabed, in shallow or deep water. Oil and/or gas is extracted at the seabed and then transported via undersea pipeline to a processing facility on the surface.

These subsea production systems usually consist of static components that can remain in place for decades. They can be as simple as a single well with a flow-line linked to a fixed platform, FPSO (floating production, storage and offloading) vessel or an onshore installation. Or they can be complex, involving several wells.

The subsea factory concept involves a standalone subsea production system on the seabed. It will carry out tasks that are currently conducted on the surface, such as single and multi-phase boosting, gas compression, gas-to-liquid and liquid-to-liquid separation as well as water reinjection.

Statoil needs the subsea factory because the future resources it is targeting are further from land, at greater depths and in colder and harsher environments. Indeed, the firm has stated it believes that compact separation facilities on the seabed will be a key to success in Arctic areas or deep-water areas like the Gulf of Mexico and offshore Brazil.

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Statoil's depiction of what a subsea factory will look like (source: Statoil).

In early February, Statoil presented its subsea factory concept at GE Oil & Gas's Annual Meeting in Florence, Italy. Rigzone caught up with Neil Saunders, senior vice president at GE Oil & Gas Subsea Systems, to learn how the offshore technology supplier plans to help bring about the subsea factory.

“We come at it from two ways,” Saunders explained. “We come at it from our ability to be able to be a systems and solutions provider. We understand what it takes to do that given our subsea production system capability.

“That will mean inevitably integrating our own components and it may also mean us integrating components that we get from the market, which is predominantly what’s happening right now with our competition and some of the systems that are being put together.”

Eventually this will mean GE being a one-stop shop for oil and gas operators looking to put a subsea factory together.

Article title
Rigzone talks to GE Oil & Gas about its plans to develop subsea equipment that will ultimately be used in the "Subsea Factory" envisaged by Statoil.

“Ultimately, we have a vision where we believe that we can offer a system that essentially is organically a GE system,” Saunders said. “If you think about what we have in the family beyond subsea … we have our power conversion team, we have our subsea team, so think about the components we can bring together. We also have rotating equipment, we have compressors, [and] we have pumps. All of a sudden you can see in the GE family the constituent parts of the system.”

But for the complete subsea factory to be achieved, evolution in the subsea environment needs to occur with plenty of value to be added with incremental steps.

“Before you get to the subsea factory concept there are quite a few opportunities. There’s boosting and re-injecting, then you start thinking about maybe gas-to-liquid separation, you think about liquid-to-liquid separation,” Saunders said, pointing out that the ultimate goal for GE will be subsea compression.

In fact, Statoil plans to realize a subsea gas compression project at its Åsgard field in the Norwegian Sea in 2015. The reason for this is that the pressure in Åsgard's fields will become too low by the end of 2015 to avoid unstable flow and maintain a high production profit to the Åsgard B platform. Compression will be needed to ensure a high gas flow and recovery rate.

For now, though, GE’s subsea entry position is focused on boosting and pumping.

“As you can imagine, with the technology we have at our disposal we are developing a range of pumps: a single-phase pump in 2015/16, a gas-tolerant pump the following year and then a multi-phase pump in 2017/2018,” Saunders said.

“In the meantime there are pumps available in the market, and we potentially can provide a system using those component parts as our competition do.”

Once the subsea factory itself is achieved, it will need to run with minimal downtime. This will involve some clever thinking and GE believes it has a key part of the solution with its Industrial Internet work in the oil and gas arena.

Saunders explained that a conventional subsea production system already has a lot of extensive monitoring.

“But in actual fact, when you think about what’s happening down there, I wouldn’t say it’s a ‘passive environment’ but there are no rotating machines, there are no real-time decisions that are being taken in a subsea environment [currently]. The data is extensive and it comes back, and there is a loop that is closed to control the subsea production system,” he said.

“Then, when you think of the subsea factory and you think about what’s happening in that context, you have rotating machinery on the seabed. So you really have a need to understand what’s happening real-time, process-wise in terms of the phases that you have, understanding how your separation might be working, understanding how your pump is performing, etc, etc.

“And then you are taking that need for data to another level, where potentially you want to make quicker decisions and you absolutely need to have that data to analyze on a much more frequent basis. That’s how we think about applying the Industrial Internet. It’s something the company does very well elsewhere with rotating machinery in terms of remote monitoring and diagnostics. And we see a subsea factory takes the need for monitoring and real-time analysis to another level.”

This is because when managing the subsea factory, operators will not be able to simply install static components that can be expected to work for decades and forget about them.

“The intervention around the subsea factory concept does need more thought than what you see in a conventional subsea production system. Ultimately the design life of a conventional system right now could be as long as 15-20 years but we are looking to extend that and we are even now seeing specifications for a 40-year design life,” Saunders said.

“Now, with the best will in the world, a rotating machine is not going to be subsea for 40 years or 25 years… so there will be an expectation of intervention.”

This is why the Industrial Internet and analysis using sophisticated acoustic and vibration-monitoring devices will become so important. Subsea machines will be closely watched in real-time to see when they will need replacing.

“Then you can almost actually plan an outage in the same way as you would in a surface application as opposed to a kind of break/fix mentality,” Saunders said, explaining that a hot-swap style approach in which, say, a new compressor or pump arrangement is plugged into the system immediately after the old machine has been taken out.

Meanwhile, subsea factories will likely also feature some redundancy as part of their systems, using multiple trains to keep production running continuously as components and subsea machines are replaced.

According to Saunders, “That’s where the value is.”

While operators like Statoil see an additional benefit of a complete subsea factory in that fewer workers will be needed to make it function when compared to conventional subsea production systems, Saunders is quick to point out that the job of engineers involved in the design of subsea systems is about to get a lot more interesting.

“The prospect of designing pressure-containing equipment is one thing,” he said. “The prospect of designing a subsea factory that is pressure-containing, process-managing and has rotating machinery is taking subsea engineering to another place, which is pretty exciting.”



WHAT DO YOU THINK?


Generated by readers, the comments included herein do not reflect the views and opinions of Rigzone. All comments are subject to editorial review. Off-topic, inappropriate or insulting comments will be removed.

Billy Joe Brewer III  |  February 26, 2014
I think this is very cool! However it could be very dangerous if anything goes wrong down there, they will need to have major safety precautions in place to make sure that a MASSIVE OIL SPILL does not contaminate the water!!! (obviously)


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