A mini-review of the application of surfactants in crude oil pipeline transportation

Due to the numerous and widespread oil fields worldwide, the main components of the produced crude oil vary significantly. However, after years of research and analysis by researchers, it is believed that four main fractions in crude oil have the greatest impact on its low-temperature fluidity, namely saturated hydrocarbons, aromatic hydrocarbons, resins, and asphaltenes. During the transportation of crude oil, surfactants have always played an important role. This article elucidates the mechanism of surfactants in crude oil transportation, summarizing the recent years' application and development progress of various surfactants in the transportation of heavy crude oil and waxy crude oil. This analysis indicates that using a single surfactant alone has a certain effect on reducing the pour point and viscosity of crude oil, but the effect is limited. To improve the pour point and viscosity reduction effects of surfactants, it is necessary to modify the surfactants. Research shows that introducing an appropriate amount of polar groups into surfactants can significantly reduce the viscosity of heavy crude oil. Based on the carbon number distribution of paraffin in waxy crude oil, introducing side chains of appropriate length into the surfactant can greatly enhance its pour point reduction effect.