The thixotropic behavior of W/O waxy crude oil emulsion

The products of offshore oil fields are mostly crude oil of high wax content. W/O waxy crude oil emulsion is a common existence state of the medium in oil-water mixed transmission pipelines, and its thixotropy is the important basic data for the shutdown and restart calculation and pumpability assessment of pipelines. Hysteresis loop is one of the methods to characterize the thixotropic behavior of materials. In this paper, the thixotropic behavior of gelled W/O crude oil emulsion near the condensation point temperature was investigated in the loading mode of increasing and then decreasing the stress linearly to form the hysteresis loop. It is indicated that the thixotropy of W/O waxy crude oil emulsion gel is not dependent on the loading conditions. With the increase of water content, the area of hysteresis loop and the hysteresis loop area ratio which reflects the structural recovery decrease, the thixotropic behavior weakens and the recovery degree of gelled system diminishes, for the presence of dispersed phase droplets hinders the recovery of wax crystal network structure.