Solubility and Rheological Properties of Live Crude Oils

Abstract:

Multiphase transportation of the wellhead product in a single pipeline is widely used in oilfields. The oil samples transported in the multiphase pipeline are often live oils saturated by light alkanes. To support the multiphase pipelining more efficiently, in this paper, the solubility and rheology of Chang10 live crude oils are studied at the pressures range from 0 to 2.0 MPa. It was found that the dissolved gas in the live oils is mainly composed of methane (32.70 vol% at 1MPa), ethane (19.43 vol% at 1MPa), propane (21.42 vol% at 1MPa) and C4+ component (22.50 vol% at 1 MPa). The gas-oil ratio, Rs, of the live oils increases rapidly with the increase of saturation pressure. However, the effect of saturation temperature on Rs is very small. The pour point, abnormal point, WAT, viscosity/equilibrium viscosity and yield stress of the live oils decrease obviously with the increase of saturation pressure, meaning that the rheological properties of the live oils improve greatly by gas dissolving. The rheological properties of the live oils are improved mainly by the dilution effect of the dissolved gas.

• Periodical: Advanced Materials Research (Volumes 524-527)
• Pages: 1881-1888
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.524-527.1881
• Online since: May 2012
• Authors: Fei Yang, Chuan Xian Li, Bing Huan Xia, Yan Bo Lu
• Keywords: Gas-Oil Ratio, Live Oils, Pour Point, Rheology, Solubility, Viscosity, Yield Stress

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