Relationship between waxy crude viscosities and wax crystal microstructure

Abstract

It is important and profound to quantitatively study the relation between rheology and microstructure for development of the microstructural mechanism of crude oil rheology and even for the waxy crude oil pipelining. However, due to the high complexity and irregularity of wax crystal morphology, quantitative characterization is hard to achieve. This has hampered further study on the rheology—microstructure relationship. A new approach combined the fractal geometry and the stereology theory is presented for quantifying the intricate wax crystal morphology and structure. Based on the characterization, the effects of microstructures and oil composition on the waxy crude viscosities are analyzed quantitatively. It further validates the previous qualitative research and enriches understanding into the microstructural mechanism of waxy crude oil rheology.

Keywords

waxy crude oil / apparent viscosity / wax crystal / morphology and structure / quantitative analysis

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