Measuring device for moisture content and mineralization degree based on plug-in impedance sensor

Abstract

The invention relates to a measuring circuit for moisture content and mineralization degree based on a plug-in impedance sensor. The measuring circuit is used for measuring moisture content and mineralization degree in an oil-water two-phase flow pipeline. The measuring circuit comprises an impedance sensor, a signal processing unit, a demodulation unit and a calculating unit; the impedance sensorcomprises an exciting measuring electrode and two protecting electrodes; the exciting measuring electrode is simultaneously served as an exciting electrode and a measuring electrode; the protecting electrodes are fixed above and under the impedance sensor; the signal processing unit comprises a front-end amplifier, a coaxial cable, an alternating current signal generator and a differential amplifier; a negative input end of the front-end amplifier is connected with the exciting measuring electrode in the impedance sensor through a coaxial cable signal wire; a positive input end of the front-end amplifier is connected with the alternating current signal generator and meanwhile is connected with the two protecting electrodes in the impedance sensor, a shielding layer of the coaxial cable and the negative input end of the differential amplifier; a standard resistor is connected with the negative input end and output end of the front-end amplifier; the output end of the front-end amplifier is connected with the positive input end of the differential amplifier.

Description

technical field [0001] The invention relates to the field of oil field exploitation, in particular to a measuring device for water content and salinity based on a plug-in electrical impedance sensor. Background technique [0002] The development of today's society has an increasing demand for energy, and oil, as the "primary energy source", plays a very important role in the national economy and national strategy. However, petroleum is a non-renewable energy source, so it is of great significance to minimize mining losses and make full use of resources during the mining process. In petroleum engineering, in order to improve the extraction efficiency of crude oil, high-pressure water injection and polymer injection technologies are often used in the secondary recovery of oil wells. However, this process makes the extracted crude oil contain water, resulting in the common occurrence of oil-water two-phase flow in the process of oil well exploitation and post-exploitation tran...

AI Technical Summary

Problems solved by technology

Although the excitation field distribution of this kind of electrode is uniform, there are problems such as the edge effect of the force line, the electrode facing area, and the electrode spacing are difficult to determine. It is suitable for square pipes; although the opposite wall arc electrode solves the problem of parallel plate electrodes, it also causes The distance distribution between the electrodes is uneven, that is, the distance between the middle of the electrodes is far and the distance between the electrodes is close, resulting in uneven distribution of the excitation field, which affects the measurement information; the mesh electrode structure can better reflect the full pipeline cross-section at the same time In addition, cross-sectional multi-electrode (such as EIT imaging technology) can also accurately measure the distribution of two-phase flow in the pipeline, but both have the problems of complex structure, inconvenient installation and high cost

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