Remote Characterization of Produced Water via Subsea Multiphase Metering

Abstract

Abstract Multiphase flowmeters (MPFM) are used to measure oil, water, and gas volumetric flow rates in real time without phase separation. Field-proven MPFM play an important role in oilfield operations as the trusted flow measurements enable production optimization and flow assurance. However, accurate multiphase flow metering requires knowledge of the reservoir fluid properties. Therefore, operators require reliable methods to keep the MPFM configuration updated and representative of the production fluids. This is particularly important for subsea fields where physical access to the MPFM can be difficult. This paper describes a successful remote water-phase characterization leading to reconfiguration of a dual-energy spectral gamma ray MPFM for an oil well in a deepwater field offshore Ghana. Reconfiguration of the MPFM was performed using data from when the well was shut in and the flowmeter venturi throat was filled with water at static flow conditions. The data was taken from Subsea Live data-driven performance service from OneSubsea (the vendor), which offers real-time data for health, operational and production insights for subsea assets. The mass attenuation coefficients for water were updated in the MPFM configuration to more representative values, determined using historical data. After the remote reconfiguration, the reconfigured MPFM demonstrated good accuracy when benchmarked against topside separator measurements, showing a proper agreement between the estimated in-situ values using historical flow metering data and the experimental measurements for both high energy and low energy water mass attenuation coefficients.