Canyon Express Subsea Multiphase Flow Metering System: Principles and Experience

摘要

As Canyon Express is a multi-field, multi-operator, deepwaterrnsubsea, gas development flowing into a common transportrnsystem, relatively accurate and reliable measurement of thernproduced fluids is essential to allocate hydrocarbon gasrnvolumes per field and to estimate system water production.rnThus, the metering principles and limitations must bernunderstood to ensure that volumes are being calculated asrnaccurate as possible. This paper describes the application,rncalibration testing, deepwater marinization program, andrnsubsequent implementation of the subsea multiphasernflowmeters used for the Canyon Express development in thernGulf of Mexico. This includes description of the meter theory,rnenvironmental condition development, and calibration. Thernoverall objective of the metering will be discussed along withrnhow the limitations of the meter affect the computation of thernflow rates for the different phases of the produced fluid andrnthe interrelationship of the engineering and testing results withrnthe actual operation of the meter including the affect of liquidrnloading on the meter performance.rnSuccessful demonstration and implementation of thernsubsea multiphase meter suitable for deepwater applicationrnallows for the measurement of hydrocarbon gas at thernwellhead thus permitting the measured gas to flow into arncommon flowline to be commingled with other productionrnstreams for transportation to a host platform. This allowsrnmultiple marginal subsea fields, each with different owners, tornbe operated as a single economic development whilernmaintaining acceptable gas measurement for allocation ofrnhydrocarbon gas volumes. The Canyon Express team alsornutilized its meter development experience in managing therndevelopment of API Recommended Practice RP85 on “SubsearnWet Gas Meter Allocation Measurement”.