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Learning from Norway Zolotukhin: Three decades of technical innovation in Arctic oil, gas projects Alan Bailey Petroleum News
In three decades Norway’s offshore oil and gas industry has mushroomed from a zero base to the forefront of technical achievement. And the country’s example of learning through practical experience and using cutting edge technology can point the way on how to move forward in exploring new frontiers on the Arctic continental shelf, Professor Anatoly Zolotukhin, deputy rector on international affairs at Gubkin Russian State University of Oil and Gas, told a meeting in the University of Alaska Anchorage Institute of Social and Economic Research on April 29.
Following the initial discovery in 1969 of the North Sea Ekofisk oil field the Norwegian industry moved into an era of huge offshore production platforms standing on the seafloor under their own weight, Zolotukhin said. Ekofisk and the Frigg gas field were in production by 1979, by which time the Stafjord oil field and Troll gas field had been discovered.
Troll went into production with an offshore platform that achieved a record as the biggest structure ever moved by “Man on Earth,” Zolotukhin said.
Gas pipelines In 1985 the opening of the Statpipe pipeline brought gas from the Stafjord area to the Kårstø receiving terminal in Norway, north of Stavanger. The Troll-Sleipner pipeline system started up in 1999, Zolotukhin said. And by 2007 a spider’s web of pipelines in the North Sea and the Norwegian Sea delivered gas from various offshore fields to European markets.
Around 2000, as Norwegian oil and gas development moved north into the deeper waters of the Norwegian Sea, a new era arrived, involving the use of ships, semi-submersible platforms and subsea templates, Zolotukhin said.
The Åsgard oil and gas field, for example, uses a ship-based floating production system. In this arrangement the ship with the production facilities encases a vertical turret containing the risers to the subsea wells. In the event of a severe storm, the turret can be detached and left semisubmersed, while the ship moves away from the site, Zolotukhin said.
Snohvit The Snohvit gas field in the Barents Sea uses remotely controlled subsea wellheads, the latest progression in offshore technical development.
The wellheads connect to umbilical pipelines that feed into a main subsea pipeline that carries products to processing facilities on an island at Hammerfest on the Norwegian Sea coast. All field structures lie on the seafloor, operated from the land and maintained by remotely operated subsea vehicles.
The Snohvit design resulted from a 17-year debate in the Norwegian parliament regarding the concerns of fishermen about Barents Sea oil and gas development, Zolotukhin said.
“(The fishermen) didn’t like platforms. They didn’t like ships. They didn’t like thrusters,” Zolotukhin said.
The huge Ormen Lange gas field in the southern Norwegian Sea is also pioneering the use of remotely controlled subsea well completions tied by pipeline to onshore facilities. From the onshore plant a long subsea export gas pipeline crosses the North Sea to Easington on the east coast of England.
And in a new twist on subsea technology, the Tordis field is pioneering the use of subsea fluid separation, with produced water being injected back into the reservoir from a seafloor facility.
Pipeline flow assurance The use of subsea pipelines from producing fields has required technologies for flow assurance, to keep fluids moving through the pipeline even in low temperatures, Zolotukhin said.
But he said that whereas there are technical limitations on subsea pipeline lengths for carrying multiphase fluids, natural gas can be piped over great distances. However, as the amount of condensate in the gas increases, the maximum pipeline length becomes less.
“If the main phase is gas, then it’s not a problem to extend the existing (distance) records,” Zolotukhin said. Snohvit set a record distance 125 kilometers and a 420 kilometer pipeline is being built this year, he said.
But the Shtokman field that is earmarked for development in the Russian Barents Sea lies 550 kilometers from land. That distance is too great for the transportation of Shtokman products through a subsea pipeline using current technology, Zolotukhin said.
On the other hand, it ought to be possible to move products to shore from a Chukchi Sea field that is, say, 50 miles offshore northern Alaska, Zolotukhin commented.
Enhanced recovery The Norwegian oil industry has also made use of advances in enhanced oil recovery, with techniques such as water-alternating-gas and carbon dioxide injection, Zolotukhin said. That has resulted in particularly aggressive targets for total oil recovery — target recoveries of 70 percent of in-place oil for the Stafjord field and 65 percent for the Gullfaks field, for example. Those percentages compare with a worldwide average of 34 percent recovery, he said.
Statfjord has already achieved 68 percent recovery and is on course for that 70 percent target, Zolotukhin said. A new concept is the injection of bacteria into a reservoir to further increase oil recovery, he said.
Drilling technologies have also made huge strides. The use of single-diameter wells with expandable casing has reduced drilling costs and drilling waste, Zolotukhin said. And, as in Alaska, the Norwegian industry makes extensive use of directional and sidetrack drilling.
In a new drilling concept, a device called a Badger Explorer would bore its way through the subsurface at the end of a cable, with the crushed rocks closing up behind it. The technique would eliminate the need for wells and drilling rigs and could cut exploration drilling costs by a factor of 10, Zolotukhin said.
Safety paramount Although the Norwegian industry has forged ahead with new technologies, stringent standards for health, safety and the environment underpin all activities, Zolotukhin said.
Zolotukhin attributes this environmental culture in part to the transparency of companies with state ownership, like StatoilHydro, and in part to government regulation of the industry. Norwegians want the oil industry to meet tough environmental standards, he said.
And strict regulation has also forced technical innovation in fields such as Snohvit, Zolotukhin said.
Norway’s carbon dioxide legislation, for example, has driven the development of techniques for carbon dioxide extraction and re-injection — in Snohvit carbon dioxide separated onshore from the gas production is piped back offshore for underground sequestration. And the country has established a target of zero discharges into the sea from drilling activities, Zolotukhin said.
StatoilHydro has a track record of using many more substantial innovations than are used on average worldwide, Zolotukhin said.
Culture of learning Zolotukhin attributed the Norwegian oil industry’s rapid growth since its inception 30 years ago in part to a culture of learning.
“They learned it the hard way because there were no specialists 30 years ago. … Now it’s one of the most advanced nations of Europe,” Zolotukhin said. “… You will never see a Norwegian coming to a meeting without a notebook. … They’re still on a learning curve.”
And that’s the kind of attitude that Zolotukhin thinks will be needed to meet the huge challenges of developing new oil and gas frontier provinces in the offshore Arctic. But Zolotukhin also thinks that the massive costs, technical difficulties and the need for specialist expertise in the Arctic will require international cooperation and an industrywide approach.
A single company cannot overcome all of the challenges alone; nor can a single country, Zolotukhin said.
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