Emulsification behaviors of crude oil-water system and its quantitative relationship with exergy loss rate

• Published in: Journal of petroleum science & engineering 2019-05, Vol.176, p.502-508
• Main Authors: Wen, Jiangbo, Luo, Haijun, Long, Zhiqin
• Format: Article
• Language: English
• Subjects: Crude oil-water system; Emulsification behaviors; Exergy loss rate; Flowing; Mixing degree coefficient
• ISSN: 0920-4105; 1873-4715
• DOI: 10.1016/j.petrol.2019.01.082

Emulsification behaviors of crude oil-water system has significant effects on flow pattern and pressure drop of crude oil-water two phase flow. The degree of emulsification, which is greatly affected by shearing intensity, water volume fraction and temperature, can be characterized by emulsified water fraction under flowing conditions. There are eight crude oils were used in emulsification experiments by stirring to study the effects of shear rate, water volume fraction and temperature on the emulsified water fraction under flowing conditions. Complete emulsification was observed below a critical water volume fraction, with the emulsified water fraction equal to the water volume fraction of the system; while there was only incomplete emulsification when the water volume fraction was higher than the critical value, with the emulsified water fraction less than the water volume fraction of the system. A mixing degree coefficient cm was proposed to characterize the mixing effect of crude oil-water system. It was found that the value of cm getting more close to 1.0 meant the better mixing effect, if not, the mixing effect was worse. For incomplete emulsification, the exergy loss rate during stirring was found to characterize the effects of shear rate, water volume fraction and temperature on the emulsified water fraction under flowing conditions in the unified way. Further, a power law correlation was proposed between the emulsified water fraction under flowing conditions and the exergy loss rate, which can be applied to the process calculation of the multiphase transportation pipelines. [Display omitted] •A mixing degree coefficient cm was proposed, and the value of cm getting more close to 1.0 meant better mixing effect.•The exergy loss rate was used to characterize the effects of influencing factors on the emulsified water fraction.•The correlation between emulsified water fraction under flowing conditions and exergy loss rate was proposed.