Pour Point Depressant for Waxy Crude Oil: A Mini-Review

Background: The background of using the pour point depressant is that wax precipitation causes several challenges during oil extraction and pipeline transport of waxy crude oils, including wax deposition, plugging of the pipeline and damage to the oil drilling equipment, which, collectively, adversely impacts pipeline performance. Method: The method which used to solve the problem of paraffin deposit is adding chemical additive. The objective of adding pour point depressant is to improve the fluidity of crude oil. Addition of pour point depressants to the oil to improve the extract efficiency is an effective way to prevent the generation of waxy crystalline clusters. In this article, four mechanisms of the pour point depressants are introduced and the types of commonly used pour point depressants are classified. The effect of different functional groups and structures of pour point depressants on the wax crystal are summarized. Conclusion: In conclusion, the factors that influence polymeric efficacy include the degree of branching, molecular weight and carbon chain length. The prevention of the wax crystal formation and improvement of the low-temperature fluidity of crude oils occurs by five reaction mechanisms of the pour point depressant, including inserting, cutting off and by other means changing the manner of wax crystal growth. The wax crystal structure and doughty polar components of crude oil can adversely affect the pour point depressant action. Furthermore, this article also describes future research directions for pour point depressants as a possible guide for researchers.