Study Of Measuring Technique On Pipeline Water Content Of Crude Oil

With the exploitation of oil for years in the oil field, the high pressure effusion of the oil well makes water content in the crude oil pipeline higher. The water content of crude oil directly affects the crude oil exploitation, dehydration, transportation, measurement, marketing, and smelting etc, the inaccurate measurements of the water content will affect directly oil well and oil layer dynamic analysis, destroy the electrical field in the electric dehydrator, lower the dewatering effect and waste energy. In recent years, real-time online measurement of water content of crude oil becomes the main research direction, and a lot of achievements in scientific research are acquired. Unfortunately, most of the achievements only can be used in the measurement of oil well, measuring technique on pipeline water content of crude oil develops slowly, and there is no perfect solution.The measurement object in the paper is the pipeline water content of crude oil, through studying the domestic and international related documents, the existing several test methods of water content of crude oil are summarized and compared, the basic principles, applications, merits and shortcomings are analyzed, according to the feature of metal pipeline and comparing the two measuring technique on pipeline water content of crude oil, a new method based on electromagnetic conductance sensor is presented.A new measuring model of pipeline water content of crude oil is made, and the transmitted signal of the sensor is optimized for ultra-low frequency electromagnetic band in this model. The ANSYS simulation, which can study the magnetic field distribution, shows that the ultra-low frequency electromagnetic waves can penetrate the pipe wall into the interior of the pipeline, and provides preconditions for the possible of the method. According to the spread theory of electromagnetic field, the paper completely derives the induced voltage on the receiving coil with the low frequency sine excitation, according to the results, a simulation work using computer is used to research the relationship between the response and the excitation after the electromagnetic conductance sensor is optimized, the results show that the new method is feasible. Finally, the paper designs the hardware and software systems based on ARM and ultra-low frequency electromagnetic conductance sensor, the relevant tests and experiments are done. Compared with the theory and simulation, the experiments results further demonstrate the feasibility of the new method and provide theoretical supports for follow-up studies.