Experimental measurements of water content in crude oil emulsions by terahertz time-domain spectroscopy
Jin Wu-Jun1,2,3, Zhao Kun1,2,3, Yang Chen2, Xu Chang-Hong2, Ni Hao2, and Chen Shao-Hua2
1. State Key Lab of Petroleum Resources and Prospecting, Beijing 102249, China.
2. Laboratory of Optical Sensing and Detecting Technology, China University of Petroleum, Beijing 102249, China.
3. Key Laboratory of Oil and Gas Terahertz Spectroscopy and Photoelectric Detection, CPCIF, Beijing 100723, China.
Abstract：
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 °C 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.
JIN Wu-Jun,ZHAO Kun,YANG Chen et al. Experimental measurements of water content in crude oil emulsions by terahertz time-domain spectroscopy[J]. APPLIED GEOPHYSICS, 2013, 10(4): 506-509.
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2013, Vol. 10 
