Simulation of pipelining pours point depressant beneficiated waxy crude oil through China West Crude Oil Pipeline

Abstract

Flow properties of waxy crude oils, particularly the beneficiated waxy crude oils, are sensitive to shear history that the crude oil experienced, called the shear history effect. To simulate this shear history effect accurately is vital to pipeline design and operation. It has been demonstrated by our previous that the energy dissipation or entropy generation due to viscous flow in the shear process is a suitable parameter for simulating the shear history effect. In order to further verify the reliability of this approach, experimental simulations were conducted for three PPD-beneficiated waxy crude oils transported through the China West Crude Oil Pipeline, a most complicated long-distance- crude-oil-pipeline technically and operationally so far in China. The simulations were made by using a stirred vessel and with the energy dissipation of viscous flow as the shear simulation parameter. Comparison between the flow properties of crude oils obtained from field test and experimental simulations, it is found that the gel points and viscosities from experimental simulations are in good agreement with the field data.

Keywords

waxy crude oil / flow properties / shear history effect / experimental simulation

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