Magnetic Resonance Multiphase Flowmeter

Transcription

1 Magnetic Resonance Multiphase Flowmeter André Boer Jankees Hoogendoorn, Mark van der Zande, Rick de Leeuw, Piet Moeleker Mathias Appel, Hilko de Jong February 2015 Houston, TX

2 Content 1. Introduction 2. Principles of Magnetic Resonance 3. Magnetic Resonance for Multiphase Flow Measurement 4. Mechanical Design 5. Test Results 6. Summary and Conclusions 2

3 Introduction Magnetic Resonance technology used in many applications Medical Imaging (MRI) Magnetic Resonance (MR) could be used for measuring multiphase flow as well What is Magnetic Resonance? 3

4 Principle of Magnetic Resonance Magnetic Resonance: Experiments on Nuclei of atoms in strong Magnetic Field In most cases Hydrogen Nucleus: Proton water gas Spinning Proton has a Magnetic Moment oil 4

5 Principle of Magnetic Resonance Magnetic Resonance: When a Magnetic Field is Applied: Proton starts to Align with this Field Proton starts to Precess (Resonance Frequency) 5

6 Principle of Magnetic Resonance Magnetic Resonance: When a Magnetic Field is Applied: Proton starts to Align with this Field Proton starts to Precess (Resonance Frequency) 6

7 Principle of Magnetic Resonance Magnetic Resonance: When a Magnetic Field is Applied: Proton starts to Align with this Field Proton starts to Precess (Resonance Frequency) 7

8 MR for multiphase flow measurement Multiphase Flow Measurement: Velocity per phase (v o, v w, v g ) Fraction per phase (l o, l w, l g ) Oil Water Gas v o.. v w.. v g.. l o.. l w.. l g.. 8

9 MR for multiphase flow measurement Velocity Measurement (v o, v w, v g ): Convective decay method Excited protons are leaving the coil due to flow v o v w v g.. l o.. l w.. l g.. v = L c /t S=0 9

10 MR for multiphase flow measurement Magnetic Resonance Imaging (MRI): Apply Magnetic Gradient: Resonance Frequency function of height slicing Velocity profile, through slicing v o v w v g l o.. l w.. l g.. 10

11 MR for multiphase flow measurement Oil Water Measurement: Water and Oil fraction (and velocities) through difference in relaxation times of Water vs Oil v o v w v g l o.. l w.. l g.. 11

12 MR for multiphase flow measurement Oil Water Measurement: Water and Oil fraction (and velocities) through difference in relaxation times of Water vs Oil v o v w v g l o l w l g.. 12

13 MR for multiphase flow measurement Gas Fraction Measurement: Liquid signal >> Gas signal Calibration gives 100% filled pipe liquid signal amplitude (Hydrogen Index) Missing signal is attributed to gas fraction v o v w v g l o l w l g l 1 G l L S 100%L l L. S 100%L 13

14 MR for multiphase flow measurement Magnetic Resonance Imaging (MRI): Apply Magnetic Gradient: Resonance Frequency function of height slicing Repeat previous steps per slice: Composition profile v o v w v g l o l w l g Gas Oil Water 14

15 Mechanical Design Ambient temperature: -40 F to F, process temperature: 212 F All electronics mounted on the meter in two flame-proof boxes Length approximately 11.5 ft. 15

16 Mechanical Design 16

17 Test Results Multiphase test facilities (10 sessions): SwRI (TX, USA) Donau Shell (NL) XCaliber (NL) DNV GL (NL) 17

18 Test Range Flow map: Test Results Parameter range: Pressure: psi Temp.: o F Salinity: oz/l Viscosity: 1-45 cst 18

19 Test Results Test Results DNV-GL (Flow Map): p=440 psi(g), T=86 F, n=4.1 cst, Salinity=1.45 oz/l Gas result : Good performance on gas No particular area where performance is worse Liquid result: Good performance on liquid Increasing error at GVF=0.99 (outside application range) 19

20 Summary and Conclusions Magnetic Resonance technology is a very direct way of multiphase flow metering One single measuring principle, direct molecular measurement Good performance over the entire test range Good performance at high WLR No systematic dependency on salinity and GVF (for values < 0.95) Gas / Liquid flow rate (12 < Qv [GPM] < 660 ) in 4 pipe Various flow regimes (incl. slug) can be measured by Magnetic Resonance First installation on oil wells in the Netherlands Commercially available 20

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