Crude Oil Moisture Content Measurement System Based On Capacitance Method Research

Crude oil moisture analyzer is an important testing instrument of thepetrochemical industry, the detection of water content of crude oil is animportant process of the process of oil field production, dehydration, storage andtransportation, and has an important significance of oil production processoptimization, flow measurement and control decision-making, gathering andtransportation. Oil to water phase flow system is extremely complex and is anonlinear dissipative dynamical systems, the mechanism of its formation, thelaw of motion has not been fully recognized, resulting in sub-phase holdupmeasurements difficult to meet the needs of oilfield has not accurately moisturecontent measurement instruments. Therefore, the real-time accurate measuringof crude oil crude oil moisture becomes the oilfield needs urgent problem.This article describes a study of the status quo and development trend ofcrude oil moisture measurement techniques, the introduction of the system ofanalysis used crude moisture detection method. Because the difference of thedielectric characteristics of the oil and water is relatively large, the relativedielectric constant of the oil is about2.3, while the relative dielectric constant ofthe water is about80, and the dielectric constant of the oil-water mixture of thedifferent moisture contents different select for measuring the electricalcharacteristics of the capacitor, so this method for the detection of moisturecontent, build a water content of crude oil detection system using coaxialcylinder capacitance sensor, with detailed descriptions of the hardware circuitdesign and software processes. The hardware design include: capacitive sensordesign RC oscillator circuit, capacitance-voltage conversion circuit, temperaturemeasuring circuit, liquid crystal display circuit, keyboard keys, circuits, memorycircuits, power supply circuit. The software design includes: the main programdesign, data collection routines, data algorithm subroutine, display and store thesubroutine, interrupt subroutine, temperature compensation subroutine and erroranalysis procedures.