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Operator shifts monitors to Anchorage Relocation of trans-Alaska oil pipeline Operations Control Center nears completion as Alyeska Pipeline embraces more system upgrades Rose Ragsdale For Petroleum News
With the flip of a switch early Jan. 23, controllers working in a Government Hill office officially took charge of managing the round-the-clock flow of crude and natural gas liquids through the trans-Alaska oil pipeline.
For Alyeska Pipeline Service Co., the critical milestone in relocating its Operations Control Center to Anchorage from Valdez came after more than five years of planning but only about 10 days of both sites operating in parallel, sharing the 24/7 duties since Jan. 13, according to Jarid Kling, coordinator of Alyeska Pipeline’s oil movements department.
“Things went smoothly, and we’re now fully operational in Anchorage,” Kling told Petroleum News Feb. 5.
The move, part of a $2.5 million project that includes building a backup control center in Wasilla, presented few technical challenges, given that remote control of pipelines is relatively common in the oil and gas industry since the advent of fiber optics. The former control center in Valdez actually functioned as a remote operation despite its close proximity to the pipeline’s terminus, Kling said.
The original system location was based on a lack of commercial infrastructures such as telecommunications when the pipeline was built in the 1970s, according to Mike Joynor, Alyeska Pipeline’s vice president of oil movements.
“New control and telecommunications systems have overcome geographical boundaries and allow the integration of technologies that provide improved access and sharing of data from a centralized location,” Joynor said when the relocation plan was first announced several years ago.
In the Lower 48, operators now routinely control multiple pipelines from more than 1,000 miles away, Kling said.
AT&T offers Government Hill offices In evaluating all options, planners say it made sense for Alyeska Pipeline to relocate the control center to Anchorage for reasons ranging from construction costs to the proximity of work groups.
While negotiating a telecommunications contract with Alyeska Pipeline, AT&T offered the pipeline service company an opportunity to lease 7,000 square feet of space in its Government Hill offices near downtown Anchorage.
Moving the OCC to Anchorage is part of a much larger restructuring program under way at Alyeska Pipeline aimed at upgrading and streamlining operations in response to declining petroleum production from North Slope. The 800-mile pipeline currently moves some 700,000-800,000 barrels per day of ANS crude and other liquids. That’s down about two-thirds from peak production of 2.1 million bpd in 1989.
Upgrades at Pump Station 3 Originally planned for 2005 or 2006, the OCC move ended up being deferred until other changes planned for the pipeline’s pump stations during the broader restructuring were completed, Kling said.
Alyeska Pipeline told the Joint Pipeline Office that its latest structural changes took place at Pump Station 3 in December and early January when oil flowing through the pipeline was switched to new equipment, including Siemens turbine generators.
On Jan. 7, Pump Station 3 was temporarily switched back to the old equipment because the inlet air heaters for turbine combustion air were not functioning properly.
Siemens worked with Alyeska to retrofit a solid sheet metal vane within the existing duct that circulates air more efficiently, reducing temperature stratification. Both turbine generators have now been modified and the first resumed operation Jan. 14, the JPO said in a recent report.
“Since the restructuring, the new pumps and stations are a lot more flexible, operator-friendly and responsive in terms of ramping up and down the flow of oil,” observed Kling.
More changes are planned for other pump stations, with the entire restructuring program scheduled for completion in 2010.
Redundancy key to reliability Since 2002, Alyeska Pipeline has relied on different telecommunications networks — two digital microwave systems operated by AT&T and a fiber optics system managed by GCI.
The upgrades gave the pipeline ground-based and microwave-based telecommunications systems and enabled Alyeska Pipeline to develop primary, secondary and tertiary communication links. Alyeska now has analog and digital microwave, fiber optics and digital satellite telecommunications available.
The three different levels of communications circuitry to the pump stations means that if any one system fails, Alyeska’s controllers will retain their ability to see what is happening on the pipeline. In addition, the satellite link has proven to be very useful in maintaining communications at high elevations such as Atigun Pass.
Alyeska Pipeline is also establishing at least three different communications routes for its networks between the pipeline and Anchorage.
But the redundancy doesn’t stop there.
The OCC equipment in Valdez will be moved to the backup site in Wasilla. Construction already under way for the redundant post should be completed within weeks and “what we call the ‘Alternate OCC’ should be operating by March or April,” Kling said.
All these changes mean the OCC can get as close to 100 percent reliability in operations as humanly possible, planners say.
The Anchorage move, meanwhile, will allow OCC controllers to work more closely with oil movements and scheduling teams, including hydraulics and automation engineers already based in Anchorage or who work in Fairbanks and can more easily travel to Anchorage than to Valdez, Kling said.
Ironically, controller preference was not a major factor in the relocation decision. Alyeska Pipeline has 12 controllers and four supervisors. Some of them have decided to continue residing in Valdez and commute to their jobs to Anchorage, Kling said. Others live in Anchorage and one resides in Florida, he added.
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