Predictive model for wall sticking onset temperature in high water cut crude oil pipes based on dynamic equilibrium of droplet distribution

Le résumé fourni par la source

During the high water cut period of oilfield development, conventional heated gathering and transportation systems incur exponentially rising energy consumption. The Wall sticking onset temperature (WSOT) is the key boundary parameter for low-temperature gathering and transportation. However, its predictive remains challenging owing to insufficient understanding of the wall sticking mechanism. Traditional WSOT predictive models commonly use Sauter mean diameter to simplify the droplet size distribution, ignoring the multiscale effect of the distribution width on the interfacial adhesion, which results in limited predictive accuracy under complex working conditions. In this study, we used a combination of cold finger experiments and microscopic observations to reveal for the first time the correlation mechanism between the WSOT of high water cut crude oil and the characteristics of the log-normal distribution of droplets in the oil-water mixture system. Based on the dynamic force balance theory, we innovatively proposed a dynamic correction method for the equivalent adhesion radius based on the dynamic distribution parameters (geometric mean and standard deviation), which breaks through the limitation of the traditional Sauter mean diameter to characterize a single scale only, and establishes a predictive model of WSOT considering the characteristics of droplet distribution. The model validation showed that the predictive error was ≤ ±4.802 %, which was significantly better than the model based on Sauter mean diameter. It is further found that regulating the water cut and shear rate can significantly reduce the WSOT by refining the droplet size and narrowing the distribution, which provides a new theoretical tool for the optimization of low-temperature gathering and transportation process.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.