Effect of pour point on wax deposition under static cooling conditions

Abstract

With the production of offshore oil and gas, wax deposition in multiphase crude pipelines has become a critical item for flow assurance. The emulsion pour point had a close relationship with the water cut of production liquid and made a significant effect on wax deposition. The investigation of the effects of water cut, pour point, and deposition enduring time on the wax deposition amount and the deposit components was conducted with static cold finger facilities. It was suggested that the effects of molecular diffusion and gelling on deposit thickness in oil-water emulsion are closely related to emulsion pour point. At a constant temperature, the function of molecular diffusion plays a leading role when it is at a low water cut and pour point. Otherwise, the function of gelling plays a leading role. This investigation offered a reference for the development of models for predicting oil-water two-phase wax deposition in the future.

Research on the Prediction of Wax Deposition Thickness on Pipe Walls Based on the Optimal Weighted Combination Model

“…In the process of pipeline transportation, when the wall temperature is lower than the oil temperature, as well as being lower than the wax appearance temperature of the crude oil, the wax molecules in the waxy crude oil will move towards the pipe wall and deposit on the pipe wall [2,3]. Wax deposit sediment reduces the transportation capacity and causes pipeline blockages in severe cases, which pose many safety hazards to the transportation of crude oil [4][5][6][7]. Therefore, mastering the wax precipitation characteristics and wax deposition laws of waxy crude oil has always been a focus of attention for scholars both at home and abroad [1,8,9].…”

The Study on Calculation Method of Temperature Distribution of Tested Tube for Wax Deposition Experimental Loop

“…Under the effect of this concentration difference, the wax molecules migrate to the wall of the tube and deposited on the wall of the tube (Hsu et al, 1994;Hunt et al, 1962;Wang et al, 2015;. The deposition of waxy crude oil has been a difficult problem that affects the safe and economic operation of the pipeline (Huang Z, et al, 2006;Hoffmann et al, 2010;Yang et al, 2014;Wang et al, 2013;Zhou et al, 2016). With regard to the process and mechanism of wax deposition in the tube, scholars generally believed that molecular diffusion is the main mechanism of wax deposition.…”