The Flow-rate Measurements in a Multi-phase Flow Pipeline by Using a Clamp-on Sealed Radioisotope Cross Correlation Flowmeter

투과 감마선 계측신호의 Cross correlation 기법 적용에 의한 다중상 유체의 유량측정

  • Kim, Jin-Seop (Korea Atomic Energy Research Institute, Radioisotope Research Division) ;
  • Kim, Jong-Bum (Korea Atomic Energy Research Institute, Radioisotope Research Division) ;
  • Kim, Jae-Ho (Korea Atomic Energy Research Institute, Radioisotope Research Division) ;
  • Lee, Na-Young (Korea Atomic Energy Research Institute, Radioisotope Research Division) ;
  • Jung, Sung-Hee (Korea Atomic Energy Research Institute, Radioisotope Research Division)
  • 김진섭 (한국원자력연구원 동위원소이용기술개발부) ;
  • 김종범 (한국원자력연구원 동위원소이용기술개발부) ;
  • 김재호 (한국원자력연구원 동위원소이용기술개발부) ;
  • 이나영 (한국원자력연구원 동위원소이용기술개발부) ;
  • 정성희 (한국원자력연구원 동위원소이용기술개발부)
  • Published : 2008.03.31

Abstract

The flow rate measurements in a multi-phase flow pipeline were evaluated quantitatively by means of a clamp-on sealed radioisotope based on a cross correlation signal processing technique. The flow rates were calculated by a determination of the transit time between two sealed gamma sources by using a cross correlation function following FFT filtering, then corrected with vapor fraction in the pipeline which was measured by the ${\gamma}$-ray attenuation method. The pipeline model was manufactured by acrylic resin(ID. 8 cm, L=3.5 m, t=10 mm), and the multi-phase flow patterns were realized by an injection of compressed $N_2$ gas. Two sealed gamma sources of $^{137}Cs$ (E=0.662 MeV, ${\Gamma}$ $factor=0.326\;R{\cdot}h^{-1}{\cdot}m^2{\cdot}Ci^{-1}$) of 20 mCi and 17 mCi, and radiation detectors of $2"{\times}2"$ NaI(Tl) scintillation counter (Eberline, SP-3) were used for this study. Under the given conditions(the distance between two sources: 4D(D; inner diameter), N/S ratio: $0.12{\sim}0.15$, sampling time ${\Delta}t$: 4msec), the measured flow rates showed the maximum. relative error of 1.7 % when compared to the real ones through the vapor content corrections($6.1\;%{\sim}9.2\;%$). From a subsequent experiment, it was proven that the closer the distance between the two sealed sources is, the more precise the measured flow rates are. Provided additional studies related to the selection of radioisotopes their activity, and an optimization of the experimental geometry are carried out, it is anticipated that a radioisotope application for flow rate measurements can be used as an important tool for monitoring multi-phase facilities belonging to petrochemical and refinery industries and contributes economically in the light of maintenance and control of them.

References

  1. Xu LA, Green RG, Plaskowski A, Beck MS. The pulsed ultrasonic cross-correlation flowmeter for two-phase flow measurement. J. Phys. E: Sci. Instrum. 1998;21:406-414 https://doi.org/10.1088/0022-3735/21/4/014
  2. Beck MS. Correlation in instruments: cross correlation flowmeters. J. Phys. E: Sci. Instrum. 1981;14:7-19 https://doi.org/10.1088/0022-3735/14/1/001
  3. Slijkerman WFJ, Jamieson AW, Priddy WJ, Okland O, Moestue H. Oil companies' needs in multiphase flow metering. Proc. 13th North Seas Flow Measurement Workshop, Lillehammer, Norway, 1995
  4. Fred J. Taylor. Principles of signals and systems, McGraw- Hill, Singapore, 1994:506-528
  5. Robert P. Benedict. Fundamental of pipe flow, John Wiley & Sons, 1980:178-227
  6. Hewitt GF, Harrison PS, Parry SJ, Shires GL. Development and testing of the 'Mixmeter' multiphase flow meter. Proc. 13th North Sea Flow Measurement Workshop, Lillehammer, Norway, 1995
  7. Kim JS, Jung SH, Kim JB. In-service identification of the heterogeneous zone in petrochemical pipelines by using sealed gamma-ray sources($^{60}Co$, $^{137}Cs$). J. the Korea society for nondestructive testing, 2006;26(3) :169-173
  8. Roach GJ, Watt JS, Zastawny HW, Hartley PE, Ellis WK. Multiphase flow meter for oil, water and gas in pipelines based on gamma-ray transmission techniques. Nucl. Geophys. 1994;8:225-242
  9. 김진섭, 정성희, 김종범, 밀봉감마선원($^{137}Cs$)을 이용한 석유 화학산업의 유체이송배관 내 가동 중 이상 진단기술. 한국공업화학회, 2005;16(6):794-799
  10. Beck MS, Plaskowski A. Cross Correlation Flowmeters- Their Design and Application. Bristol: Adam Hilger, 1987
  11. Petryka L. Precise velocity measurements in two phase flow by means of sealed radioactive sources. The End-of-Mission Report to Kuala Lumpur, IAEA, RAS/8/078-06, 1998
  12. Jenkins DM, Lysak PD, Capone DE, Brown WL, Askari V. Ultrasonic cross-correlation flow measurement: Theory, noise, contamination mechanisms, and a noise mitigation technique. Proc. 14th International conference on nuclear engineering(ICONE), July 17-20, Miami, Florida, USA
  13. Mackley IG. Multiphase metering past, present and future. Proc. Sem. Multiphase Meters and their Subsea Applications, London, 1993
  14. Scheers AM, Letton W. An oil/water/gas composition meter based on multiple energy gamma ray absorption (MEGRA) measurement. Proc. 14th North Sea Flow Measurement Workshop, Peebles, Scotland, 1996
  15. Avinash C. Kak, Malcolm Slaney. Principles of computerized tomographic imaging. IEEE, New York. 1999:5-47
  16. Schneider F, Peters F, Merzkirch W. Quantitative analysis of the cross-correlation ultrasonic flow meter by means of system theory. Meas. Sci. Technol. 2003;14:573-582 https://doi.org/10.1088/0957-0233/14/5/306
  17. Leszek Petryka. Radiometric cross-correlation techniques for flow rate measurement in multi-phase system. International atomic energy agency consultants' meeting, Krakow, Poland, 2001; 22-26 Oct
  18. Van Santen H, Kolar ZI, Scheers AM. Photon energy selection for dual energy $\gamma$-and/or X-ray absorption composition measurements in oil-water-gas mixtures. Nucl. Geophys. 1995;9:193-202
  19. Tjugum SA, Hjertaker BT, Johansen GA. Multiphase flow regime identification by multibeam gamma-ray densitometry. Meas. Sci. Technol. 2002; 13:1319-1326 https://doi.org/10.1088/0957-0233/13/8/321
  20. Geir Anton Johansen, Peter Jackson. Radioisotope gauges for industrial process measurments, John Wiley & Sons, 2004:215-221
  21. Worch A. A clamp-on ultrasonic cross correlation flow meter for one-phase flow. Meas. Sci. Technol. 1998;9:622-630 https://doi.org/10.1088/0957-0233/9/4/010
  22. Thorn R, Johansen GA, Hammer EA. Review article on recent developments in three-phase flow measurement. Meas. Sci. Technol. 1997;8:691-701 https://doi.org/10.1088/0957-0233/8/7/001