A study of high viscosity oil displacement from a curved solid in aqueous solutions

• Author / Creator

  Li,Rui

• The spontaneous displacement of a fluid in another immiscible one on a solid surface is essential for many technical applications, such as painting, detergency, bitumen extraction and enhancing oil recovery. This project was motivated by exploring a process of high viscosity bitumen displaced by aqueous phase over sand grains during the water-based oil sands extraction. For the experimental investigation, a microscopic control and image system was adopted to observe the microscale spontaneous displacement of high viscosity model oil droplets over highly curved surfaces in aqueous media. Relevant characterizations (e.g., the three-phase contact angle and the three-phase contact line velocity) were extracted via digital image analysis and the corresponding methodology was discussed in detail. The interfacial tension between the high viscosity oil and aqueous solutions, was determined by the drop shape relaxation method due to the difficulty of measurements using conventional techniques of tensiometry. The experimental results showed that both static and dynamic behavior of the oil displacement could be significantly changed by surface wettability alternation or surfactant addition. On the other hand, only the displacement dynamics strongly depended on oil viscosity, surface curvature, and droplet volume. An interesting observation of the dynamic droplet shape deviating from a spherical segment has been found to originate from the relative significance of the viscous stress to the capillary stress on the interface near the three-phase contact line. The quantitative data analysis using the generally accepted models of dynamic wetting indicated that the displacement dynamics could be controlled by different mechanisms at different stages, and additional mechanisms could be introduced by surfactant additions. The findings from this study are expected to improve the general knowledge of spontaneous liquid-liquid displacement as well as offer some practical implications to optimize the bitumen liberation process during industrial operations.

• Subjects / Keywords

  • dynamic wetting
  • spontaneous displacement
  • high viscosity fluid
  • microscale

• Graduation date

  Fall 2019

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-5hdw-vt11

• License

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