The Water Cut Measurement System Research

With the process of informatization and automation in the oil industry and the oil fieldexplotation entered a high, or even very high, water cut stage, the sustainable devolopment ofoil filed is in great argency. Because of three-phase lfow measurement technology has a greatsignificance in improving the well developing eiffciency and increasing oil recovery eiffciency,the research on three-phase flow measurement is quite essential. The exsiting methods ofthree-phase lfow masurement have some drawbacks and effecting factors，which make themasurement results are not that accuracte. In addition, the situation and detection technologyand method of oil and gas water three phase lfow field is summarized. In the paper, theimplementation of water cut and lfow electrode measurement system is designed based on thetechnology of conductance measurements, and the measure pirnciple of conductance sensorwas descirbed in detail. The advantanges of scheme were low cost, simple structure, noradiation, safe and reliable, etc.The main parameters (concentration, flow, velocity, quality of share，density, pressuredrop, etc.) on three-phase lfow and the inlfuencing factors of the measurement (flow pattern,water salinity, pressure, temperature, etc.) was studied. Water cut and flow electrodemeasurement system weer established-The conductivity sensor and hardware circuit and thesotfware of the electrode measurement system were improved, aiming at dealing with the keyproblems in the system, such solutions optimized the measurement system obviously.The design and demonstration of overall measurement system scheme were completed,which was based on measuirng pirnciple of conductance array sensor. The newly establishdwater cut and flow electrode measurement system theoretical model is more suitable for thesystem, based on that, a kind of on line instrument for the measurement of the water cut andflow of the three-phase lfow was developed. The dirve signal is match the responsecharacteristics of receiver electrode. Large number of experiment were made by using theinstrument, the instrument has a flinction of sampling the water cut analog signal of themixture of water and oil and transfeirng it to host computer by means of the sampling model inthe instrument. Never the less，some problems exposed, low signal-to-noise ratio, unreliablemeasuirng results, ect. Then The suitable filter and reasonable layouts of the circuit structurecan eliminate the impact of rfequency converter in the test system and enhance the signal-to-noise ratio.Atfer abundances of indoor tests, and the expeirmental measuirng results was analysed,the veirifng results shows that the optimize structure of the improved measurement system iscompletely feasible.