Page 88 - Intelligent Digital Oil And Gas Fields

Instrumentation and Measurement 59

To separation system

Venturi meter
(total mass flow)

Gamma Dual gamma ray detectors
densitometer (to measure gas, oil and water
phase fractions
(total flow density)

P
DP Compositional Infrared spectroscopic sensors
gas meter

Temperature
sensor
T Valve

Fig. 2.11 A prototype of a multiphase flowmeters (MPFM) integrated with several
devices, such as a γ densitometer, Venturi meter, dual γ-ray detector, infrared ray spec-
troscopic meter, compositional gas devices, and temperature sensors.

Direct Flow Estimation
Direct estimation methods include compressor volumetric estimation for gas
rates and tank level variance for liquids. However, these methods quickly
lose their accuracy when multiple wells are combined to feed tanks or com-
pressors. Requires a lot of allocation and calculation processes to improve
accuracy.

Virtual Flow Estimation
Where instruments and direct estimation are not possible or economic, vir-
tual estimation can be used. Virtual estimation can be done using real-time
nodal analysis or using a data method—like a neural network—based on his-
torical well tests.