介电常数法在原油破乳剂脱水性能评价中的应用

Application of Dielectric Constant Method to Evaluation of Dehydration Performance of Crude Oil Demulsifier

研究了介电常数法在原油破乳剂脱水性能评价方面的运用情况;通过采用原油净化油分别与蒸馏水和原油污水配制不同水含量的原油乳状液,研究了原油乳状液中的水含量和矿化度对介电常数的影响。实验结果表明,原油乳状液中水含量的变化对介电常数的影响很大,当原油乳状液中的水含量达到30%(w)时,介电常数突跃变大;在一定范围内,原油乳状液的矿化度对介电常数的影响较小。经实验发现,针对某油田区块现场原油的物性及污水水质的特点模拟配制原油乳状液,通过实验绘制脱水后油相介电常数-原油破乳剂脱水率的标准工作曲线,可快捷、准确地评价原油破乳剂的脱水性能。

The dehydration performances of crude oil demulsifiers were evaluated by the dielectric constant method. Crude oil emulsions were prepared by adding distilled water or crude oil sewage to purified crude oil,and the infl uences of water content and salinity of the crude oil emulsions on their dielectric constant were studied. The experimental results indicated that the influence of the water content on the dielectric constant was more sensitive,and when the water content reached 30%（w）,the dielectric constant increased significantly. And the salinity variation had little effect on the dielectric constant to a certain extent. It was found that,the dehydration performances of crude oil demulsifiers could be evaluated fast and accurately by drawing the standard curves of the oil phase dielectric constant after dehydration-crude oil demulsifier dehydration rate according to the characteristics of crude oil and sewage from different oilfields.