Design Of The Device Of Detecting Oil-water Interface For The Field Mounted Storage Tanks

Most of oil fields in our country is in the middle and late stages of mining,because of thepressure of crude oil is continuously reduced, so need to water injection reservoir in the actualmining crude oil,then leading to higher water content ratio of crude oil.This caused greatpressure on the storage and transportation facilities, and increase theenergy consumption andwaste.Therefore, the work of crude oil dehydration is a necessary link in the oilfielddevelopment.In fact, there is an emulsion layer between the tank of crude oil and water,thislayer is composed of oil, water and emulsifier composition.It belongs to the oil-watertransition layer, the transition layer of the oil-water interface is fuzzy.The key of crude oildehydration is to find reasonable oil-water interface.To improve the efficiency and quality ofdrainage dehydration, reducing the oil spill accident,is particularly important.This paper is based on the transformation between capacitance and frequency,making theoil-water interface detection device.The use of sectional type capacitance sensor to distinguishthe tiny capacitance.And the use of LC oscillation circuit, the capacitor is not easy to detect thevalue into the frequency value.Finally, according to the different medium return frequencyvalue, to obtain reasonable oil-water interface.Describes the measuring principle and testingprocess of oil-water interface measuring device,at the same time, given the specific designscheme.And an important part of the device to do a detailed analysis.According to the detectiondevice can realize the function,meanwhile,hardware circuit mainly includes sectional typecapacitance sensor, LC oscillator circuit, frequency modulation circuit, multi-channel selectingcircuit and power supply circuit,the main controller STM32SCM as a signal acquisition andprocessing.The part of software mainly include the correct data acquisition, signal processingandthe rapid and smoothcommunicationprograms.In order to meet the production requirements of oil field, the system has been set up in thehost and from the machine,auxiliary machine to get the data results, transmitted to the hostthrough the low power wireless sensor module-ZigBee.Wireless module can be easily made upofamulti nodenetwork.Considering the actual workingconditions andthecharacteristics ofthe object to be measured,this paper introduces the natural environment of a tank modelmaking.By using the edible oil of properties similar to crude oil and water based on the modelexperiment.Ten tested the accuracy and reliability of the hardware circuit and repeatedexperiment device at the same time.Through the verification, the device is reliable and stableand for the crude oil dehydration to provide rational data of oil-water interface.MeanwhileSimplify work flow and accelerate the dehydration rate, achieved the objectives andrequirements.