Microwave monitoring of water in crude oil mixtures in the K band. Part 2. Temperature and salinity effects

Abstract

The effects of salinity and temperature on the measurement of the water content of water in oil mixtures using microwave absorption at 24.1 GHz have been investigated for North Sea crude oil, Umm Shaif (Abu Dhabi) crude oil and Quendilla 19 oil. Between 20 and 50 °C, with a sodium chloride concentration of less than 1.4 M and a water content of less than 5%, this attenuation has been shown to be [6 + 1.2M–0.1(T–30)] and [6 + 2.2M– 0.34(T–30)] dB m^–1(% aqueous phase)^–1 for North Sea and Abu Dhabi crudes, respectively (M= molarity of NaCl solution; T= temperature in °C). These results are similar to those calculated theoretically on the basis of dispersed water having the same dielectric properties as bulk water. The attenuation coefficients thus calculated are [9.4 + 1.5M– 0.12(T–30)] dB m^–1(% aqueous phase)^–1.