摘要
We measured the water content （0.01% 0.25% w/w） in crude oil emulsions using terahertz time-domain spectroscopy （THz-TDS）. To improve the precision and range of the measurements, we used 1 and 10 mm thick quartz cells. The experiments were performed at 20 ℃ and the THz wave was transmitted vertically to the samples and detected on the other side. The experimental results suggest linear relation for the THz absorption coefficient and the water content of the crude oil emulsions in the observed range. The linear dependence facilitates high-precision measurements of the water content of crude oil. This suggests the potential of THz-TDS in determining the water concentration in crude oil and borehole fluid identification.
针对目前石油勘探开发、输运检测过程中流体识别与定量表征以及原油含水率在线快速测量的难题,引入了最新的太赫兹时域光谱测量方法和技术。本文进行了一项基于太赫兹时域光谱测量原油乳状液中的含水率的试验。实验用了10 mm和1 mm两种厚度的高纯度石英样品池,两种样品池中的含水率(质量分数)分别从0.01%至8%与8%-25%,整个实验过程在恒温20摄氏度的环境下进行的。每一次测量均保证了太赫兹波垂直入射在样品上并在另一侧进行探测。实验结果表明,原油乳状液的太赫兹波段的吸收系数与含水率之间存在良好的线性关系。这种线性依赖关系既显示出实验中乳状液是稳定且均匀分布的,又为含水率的高精度测量提供了保证。通过本实验工作的开展,预示了太赫兹时域光谱技术用于原油含水率测量与地层流体识别将是一项颇具潜力的新型技术。
基金
sponsored jointly by the National Key Basic Research Program of China(No.2013CB328706)
the Special-funded Program on National Key Scientific Instruments and Equipment Development(No.2012YQ140005)
the Beijing National Science Foundation(No.4122064)
the Science Foundation of China University of Petroleum(Beijing)(No.QZDX-2010-01 and KYJJ2012-06-27)
