Abstract
The crude oils exploited in oilfields are mainly high-wax crude oils. Paraffins precipitate, crystallize, and form a three-dimensional network structure, when the temperature falls below the Wax Appearance Temperature (WAT), which decreases crude oil fluidity. This poses huge challenges to oil exploitation and transportation, as well as cost control. To date, the addition of chemical pour point depressants has been a convenient and economical method to improve low-temperature fluidity in crude oils. This article reviews the types of pour point depressants of crude oil and their performance mechanisms, and introduces the main research methods and progress made in the study of the performance mechanisms of pour point depressants in waxy crude oils. Finally, the development direction of pour point depressants is prospected.
Keywords: Waxy crude oil, pour point depressant, performance mechanisms, co-crystallization, flow behavior, rheology.
Graphical Abstract
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