Thesis Format
Integrated Article
Degree
Master of Engineering Science
Program
Chemical and Biochemical Engineering
Supervisor
Anand Prakash
Abstract
Oil-water emulsions encountered during production and refining of crude oil, as well as oil spills present technical challenges. There is need for low-cost technology to understand characteristics such as composition, droplets size distribution and other rheological properties of oils and their emulsions and monitor oil layer depth of spill.
The main purpose of the first part of this work was to develop and test ultrasonic based technology to characterize oils and their emulsions using their acoustic velocities and attenuations. The technique captured an increase in both acoustic velocity and attenuation with asphaltenes concentration in crude oil. Thus, the fast response and low-cost ultrasonic techniques provide a plausible means of monitoring this impurity level in treated and upgraded crude oils. Tests with emulsions of oil samples exhibited that both acoustic velocity and attenuation decreased with time, which indicated water droplets settling. This was confirmed by direct measurements of water separation with time which were consistent with ultrasonic results. These findings have opened a new perspective for the ultrasonic technique to monitor and characterize emulsions online.
The main purpose of the last part of this work was to develop a low-cost ultrasonic-based technique to monitor the oil layer depth of the spills. Layers of water-in-oil emulsion and mineral and crude oil samples were added to the DI water surface at an increment of 1 mm thickness in a jacketed vessel. Acoustic velocity decreased with the thickness of oils and their emulsions layers, while attenuation increased as expected. This is significant progress towards the development of ultrasonic technology to detect and monitor oil spill depth. A suitable device configuration is proposed for further development and field testing.
Summary for Lay Audience
Oil-water emulsions encountered during the extraction and cleaning of crude oil, as well as oil spills present a lot of problems. An emulsion is a mixture of two immiscible liquids which are water and oil in this case. There is a need for a low-cost way of knowing the behavior of oils and their emulsions and knowing the oil layer depth of the spill.
This study first developed and tested ultrasonic based technology (sound waves above human audible limit) to know the behavior such as composition and droplets size distribution of oils and their emulsions. It was observed that both acoustic velocity (speed of sound through a medium) and attenuation (loss of wave signal energy) increased with an increase in the amount of asphaltene (the substance that gives crude oil dark brown color) in crude oil samples. Thus, fast feedback and low-cost ultrasonic techniques provide a reasonable means of monitoring this impurity level in the treated and ready to be transported crude oils. Tests with emulsions of oils showed that both acoustic velocity and attenuation decreased with time, which indicated water settling out. This was confirmed by direct measurements of water separation with time which were consistent with ultrasonic results. These findings have opened a new perspective for the ultrasonic technique to monitor and know the behavior of emulsions online.
The last part of this study developed a low-cost ultrasonic-based technique to monitor the oil layer depth of the spills. Layers of oil samples and their emulsions were added to the deionized water surface at small increments. Acoustic velocity decreased with an increase in the thickness of oils and their emulsions layers, while attenuation increased. This is an important step towards developing ultrasonic technology to identify and measure oil spill depth. A suitable change in the shape of the ultrasonic device and how it works is proposed for further development and field testing.
Recommended Citation
Raigan, Kanu, "Ultrasonic Techniques for Characterizations of Oils and Their Emulsions and Monitoring Oil Layer Depth of Spill" (2020). Electronic Thesis and Dissertation Repository. 6997.
https://ir.lib.uwo.ca/etd/6997