Located on the Arctic Coastal Plain, 40 miles west of Prudhoe Bay, ConocoPhillips Kuparuk facility on Alaska's North Slope is the second largest oilfield in North America. At CPF1, ConocoPhillips brought on a new field with heavy oil and high solids content which necessitated upgrading the 1st Stage production separator. The original separator level instrumentation, used for the past 23 years, utilised traditional displacers and differential pressure cells for both oil and interface measurements.
In an environment where extreme winter temperatures of minus 60 deg F (-120 deg F with wind chill) are the norm then high reliability and maintenance free operation comes very high in the specification of instruments. This case study shows, with operator feedback and ‘real time’ ‘on line’ screen shots and trending data, how various novel and traditional level measurement technologies performed under these conditions of extreme temperature and dealing with difficult to separate oil with a high solids concentration. The technologies under review included the Tracerco Profiler, Guided Wave Radar, internal displacers and external differential pressure cells.
"The new technology Tracerco profiler has been extremely helpful in identifying emulsion build-up, allowing us to attack it quickly with chemicals. We have also been able to improve the interface control tuning on the water outlet valves. We have not seen much foaming, but that may be because we are treating with a lot of antifoam. The sand monitoring capability was an unexpected benefit. Operations knew all along it could see sand, but we didn't expect to use it like we have been. We anticipated sandjetting the vessel about once per week as we have for the past 23 years, but with the new heavy oil field producing an order of magnitude more than that, knowing when to sand jet (almost daily now) has been a huge advantage."