GEANT4 simulation of water volume fraction measurement in dehydrated crude oil

GEANT4 simulation of water volume fraction measurement in dehydrated crude oil 1 corresp first-author E-mail: jingchunguo@163.com E-mail: jingchunguo@163.com jingchunguo@163.com 1 1 College of Electric Engineering, Yanshan University, Qinhuangdao 066004, China College of Electric Engineering, Yanshan University, Qinhuangdao 066004, China Online measurement of water volume fraction (WVF) in dehydrated crude oil is a difficult task due to very little water in dehydrated crude oil and high precision requirements. We presents a method to measure water volume fraction in dehydrated crude oil with γ-ray densitometry. The Monte Carlo computer simulation packet GEANT4 was used to analyze the WVF measuring sensitivity of the γ-ray densitometry at different γ-ray energies, and effects of temperature, pressure, salinity and oil components on WVF measurement. The results show that the γ-ray densitometry has high sensitivity in γ-ray energy ranges of 16~25keV, and it can distinguish WVF changes of 0.0005. The calculated WVF decreases about 0.0002 with 1℃ of temperature increase and they have approximately linear relation with temperature when water volume fraction remains the same. Effects of pressure, salinity and oil components on water volume fraction can be neglected. Experiments were done to analyze sensitivity of the γ-ray densitometry. The results , as compared with simulations, demonstrate that simulation method is reliable and it is feasible to gauge low water volume fraction using low energy γ-rays. Water volume fraction Dehydrated crude oil Gamma ray densitometry Monte Carlo method Compensation algorithm References General Administration of Quality Supervision , Inspection and Quarantine of the People’s Republic of China , Standardization Administration of the People’s Republic of China . Crude petroleum-Determination of water-Distillation method. GB/T 8929-2006 , 2006 . American Society of Testing & Materials . Standard test method for water in crude oil by distillation. ASTM D4006-81(Reapproved 2005) , Washington 2005 . LI Zhibiao , WU Yingxiang , LI Donghui . Nuclear Science and Techniques , 2006 , 17 ( 2 ): 86 - 91 . Nuclear Science and Techniques Tjugum S A . Frielingb J , Johansen G A . Nuclear Instruments and Methods in Physics Research, Section B , 2002 , 197 ( 3-4 ): 301 - 309 . Nuclear Instruments and Methods in Physics Research, Section B Ouardi A , Benchekroun D , Hoummada A , et al . IEEE Transactions on Nuclear Science , 2003 , 50 ( 4 ): 1257 - 1270 IEEE Transactions on Nuclear Science Asbro E , Johansen G A , Opedal H . Nuclear Instruments and Methods in Physics Research, Section A , 1999 , 431 ( 1-2 ): 347 - 355 . Nuclear Instruments and Methods in Physics Research, Section A GEANT4 Collaboration. GEANT4 User’s Guide . http://geant4.web.cern.ch/geant4/ . GEANT4 Collaboration. GEANT4 User’s Guide Holstad M B , Johansen G A . Measurement Science and Technology , 2005 , 16 ( 4 ): 1007 - 1013 . Measurement Science and Technology Johansen G A , Jackson P . Applied Radiation and Isotopes , 2000 , 53 ( 4-5 ): 595 - 601 . Applied Radiation and Isotopes 10.1016/S1001-8042(07)60046-3 TE622.1 + 4,O657.35 2007-01-09 2007-08-20 2021-01-19 2007 Nuclear Science and Techniques 04 18