A Detailed Investigation Comparing Test Separator and MPFM (Multiphase flow meter)

Field testing can be done to determine the accuracy of Multiphase Flow Meter and how it compares to that of Test Separator. This accuracy can be tested in the measurement of the three production phases namely oil, gas, and water in addition to establishing the meter reliability in the field environment. A Multiphase Flow Meter can be described as a device utilized in the measurement of flow rates of individual phases in a specific flow in the case oil, water and gas mixtures are co-mingled in the production operations (Mofunlewi & Ajienka, 2008). A test separator, on the other hand, is a device used in the separation and metering well fluids. This essay provides a detailed comparison of the MPFM and test separator concerning their operating principles, advantages, drawbacks and economic aspects.

First, there is the comparison of the MPFM and test separators operating principle. The operating principle of an MPFM entails first measuring the flow velocity of the combined phases in addition to that of phase fractions. The obtained measurements are used in the establishment of the individual phases' flow rates (Mofunlewi & Ajienka, 2008). On the other hand, the test separator operates on the principle that there is density variation in three components. This allows for stratification when the components move from gas which is on top, water is at the bottom, and oil occupies the middle region.

These two devices also compare concerning their various advantages. The test separator's application allows retrieval of lost wells which have substantial implications on the bottom line. Also one can obtain component fluid samples, and it is not sensitive to flow regimes. Their operations are well understood, and their use permits well clean up. In comparison to test separator, MPFM has a fast response which allows more frequent testing (Eltayef, 2014). They can also avail continuous well data in real time. The use of MPFM eliminates valving and maintenance associated with test separator. There is also the elimination of instrumentation, safety measures, control and testing that is associated with test separators. There is an improvement of the fingerprinting of production features, and its efficiency is improved in addition to reduced HSE risk.

It is also important to distinguish the drawbacks between these two devices. In the situation undersized test separators are used, residence time is reduced resulting in poorer separation. There is a possibility of micro-bubbles being held in solution when dealing with viscous liquids and leading to the micro-bubbles not being separated out. Test separators are susceptible to poor maintenance and calibration (National Measurement System, n.d). There are some issues and challenges associated with MPFM. It is essential to note these drawbacks can affect other flow meters. The presence of hydrates can lead to equipment damage, and the possibility of blocking the entire pipeline is true. There are wax molecules in some oils which can lead to formation wax particles in very low production temperatures. These wax particles can block the pipelines and can lead to errors if a meter has a Venturi which can be blocked by the wax build up (National Measurement System, n.d).

The economics of these two meters can be compared. The production streams usually entail three phases namely gas, condensate, and water. For accurate measurements, one need to choose a test separator or an MPFM. The selection between these two can be made through the comparison of their prices and installation costs. The cost of a test separator is approximately between $800,000 and $1,500,000 depending on the size and pressure specifications of the device. MPFM on the other hand costs between $ 40,000 and 60,000 (Eltayef, 2014).

In conclusion, the essay has made a comparison of Multiphase Flow Meter and test separator. There has been an outline of the difference in their operating principles, advantages, and shortcomings. Their comparability is clear, and specialist can only make their selection for application in a project by considering cost, size and how compactness of a device.

References

Eltayef, A. (2014). Technical & economical comparison between installations of multi-phase test separator or multiphase flow meters on gas wells installation. Retrieved 17 September 2017, from https://www.linkedin.com/pulse/20140907075706-178610257-technical-economical-comparison-between-installations-of-multi-phase-test-separator-or-multiphase-flow-meters-on-gas-wells-installation

National Measurement System (n.d). GOOD PRACTICE GUIDE: AN INTRODUCTION TO MULTIPHASE FLOW MEASUREMENT. National Measurement System. Retrieved 17 September 2017, from http://www.tuvnel.com/_x90lbm/An_Introduction_to_Multiphase_Flow_Measurement.pdf

Mofunlewi, S., & Ajienka, J. (2008). Determination of Multiphase Flow Meter Reliability and Development of Correction Charts for the Prediction of Oilfield Fluid Flow Rates. Leonardo Journal of Sciences, (12), 1 65-17 4.