Design Of The On-line System Of Oil-water Interface Examination

Oil is the world’s most widely used energy sources, however, to the separation of oil from mined, refined, and then to industrial, life, production, consumption is an extremely complex process. The technology of oil-water separation has always been a critical and extremely complex problem during the crude oil production in the oil field, so it refers to the problem of oil-water interface examination. Because of the complexity of oil-water interface in the oilcan, when adopted the traditional capacitance sensor, it is difficult to achieve the ideal examination precision, which this disquisition is precisely in view of. The author has designed the on-line system of oil-water interface examination and control, based on the new sectional type capacitance sensor.Firstly, hardware design of the on-line system of oil-water interface examination for grain moisture is introduced in this paper, which includes analogue circuit and digital circuit. The designs of micro-capacitance detection circuit, the designs of demodulation circuit, the designs of subtraction circuit and the excitation signal source circuit in analogue circuit are described; meanwhile, a brief introduction of microcontroller, the design of sampling and clipping circuit, the design of the serial communication are also mentioned in the digital circuit. Secondly, using Visual Basic has completed a person-computer communication interface and has completed the operation including data processing, data store and data presentation to the data which was transferred from slave computer through RS-485serial port communication. Finally, In order to improve the detection accuracy of the oil-water interface, the hight-voltage characteristic curve is found by analyzing the experimental data.The characteristic of this paper includes the adoption of the sectional type capacitance sensor, the design of the simple practical capacitance examination circuit, the improvement of the arithmetic estimating oil-water interface, and the application that introduced the monitoring technology by computer into crude oil production in the oil field.