MuFA (Multiphase Fluid Analyzer) is a concept for in-situ measurements of fluid properties of subsea multiphase flow, which is applied for improving the accuracy of multiphase flow meters (MPFMs).
Multiphase meters are used to measure production from individual wells and commingled production from several wells from fields. MPFM are delivered in topside and subsea versions.
MPFMs are used for ownership allocation and/or well allocation, including for daily production optimisation.
Fluid properties (i.e. density, permittivity, conductivity of oil,gas and water) are required as input data for multiphase meters. The traditional way to obtain fluid properties is to capture samples at the outlets from test separators and get the samples analysed in laboratories. For fields or applications without test separator, it is required other solutions that can provide on fluid data needed as input to the multiphase meters.
For fields where it is expected change in fluid properties over time, input data to multiphase meters need to be updated to maintain their performance. In case fluid properties input data is not updated accordingly, the results can be significant measurement errors, which depends on the measurement systems utilized in the multiphase meters. Wrong measurements will result in poor well allocation, lost production optimisation potential, and increased economic risk in ownership allocation between licence.
The MuFA concept has been developed by NORCE and Equinor, and the purpose of MuFA is to provide updated fluid properties that update the input data to multiphase meters. MuFA is an add-on module to a MPFM that measures the required fluid parameters. This is done by sampling the multiphase flow into a subsea chamber, let the fluids separate, and measure the fluid parameters of the three phases directly at operating conditions. The fluids are released into the multiphase flow after characterization.
