Study on Thixotropic Properties of Waxy Crude Oil Based on Hysteresis Loop Area

Liping Guo, Yu Wang, Shuang Shi, Xiaoyang Yu, Xu Chen

College of Petroleum Engineering, Daqing Petroleum Institute, Daqing, China.

DOI: 10.4236/eng.2015.77043                

Abstract

Thixotropic properties are one of the low temperature rheology behaviors of gelled waxy crudes. In order to study the thixotropic behavior of gelled waxy crudes oil under cyclic loading of linear increasing and decreasing of shear rate, three different types of waxy crude oil were studied ex-perimentally by using MARSIII rheometer. It is found that hysteresis loop area could represent strength of thixotropic properties under that loading. With increasing of the rate of share rate sweep, the area of second hysteresis loop is much smaller than first one and began a slow decline from the third hysteresis loop. Areas of each hysteresis loops were decreased with increasing temperature, but it was different in decline rate—the lower the temperature, the greater the rate of decline. The maximum rate of decrease is the first hysteresis loop with exponential decline, and remaining hysteresis hoops approximately decrease linearly. In addition, based on the experi-mental results an empirical correlation is developed to describe the relationship of hysteresis loop area and rate of share rate sweep.

Keywords

Waxy Crude Oil, Thixotropic, Hysteresis Loop, Area

Conflicts of Interest

The authors declare no conflicts of interest.

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