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TransCanada PipeLines Ltd., Calgary, has begun operating the first custody transfer meter station in Canada using ultrasonic technology as the prime measurement device.
The new technology, pioneered largely in Europe, has the potential to improve the accuracy of measuring the volumes flowing through our pipeline, said Bob Reid, senior vice- president. TransCanada was one of the first in North America to recognize and test the technology for a custody transfer application and the first to present information on the technology to Industry Canada.
Two ultrasonic meters were installed at TransCanadas Success receipt meter station in Saskatchewan last month after the meters received certification from Industry Canada.
Ultrasonic advantages
Ultrasonic meters cut capital costs. TransCanada can save 10- 50% in capital costs by using ultrasonic meters on large new meter stations or meter station upgrades.
Meter station capacity at Success has increased 70% through replacement of the existing two 12 in. turbine meters with two 12 in. ultrasonic meters, thereby meeting requirements for increased volumes.
Ultrasonic meters can trim fuel costs. Costs for compressor fuel created by pressure drops across metering facilities cost the industry millions of dollars a year. Conventional type meters are responsible in part for these pressure drops, TransCanada said.
Unlike conventional meters, ultrasonic meters are nonintrusive devices that use an acoustic signal to measure the flow of gas. By changing the meters at Success and removing the gas scrubbersrequired for additional cleaning of the gas for conventional meterspressure drops will be reduced and fuel saved.
Ultrasonic meters require less maintenance because they have no moving parts. Since the meter does not have to be removed for inspection of these moving parts, this helps meet Trans- Canadas goal of reducing hydrocarbon emissions.
Tests conducted
TransCanada has been testing different ultrasonic meters for over a year at its Douglastown compressor station at Niagara Falls, Ont.
At Douglastown, a 24 in. ultrasonic meter was tested in series with four 12 in. turbine meters. The testing allowed for a direct comparison between the two kinds of meters.
The results confirmed the ultrasonic meter is accurate, reliable, and meets the requirements to be used at custody transfer points.
TransCanada will continue to explore other opportunities to add ultrasonic meters to its 13,000 km pipeline system.
Copyright 1996 Oil & Gas Journal. All Rights Reserved.
