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Role of Hydrodynamic Cavitation in Fine Particle Flotation
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- Author / Creator
- Li, Haipeng
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In this study, the criteria for both homogeneous and heterogeneous nucleation induced by hydrodynamic cavitation were investigated. The interaction of micron size bubbles with fine coal and the effects of the presence of micron size bubbles and bubble aging on bubble and fine coal attachment were examined using a model system. Furthermore, heterogeneous nucleation was investigated as a function of the hydrophobicity of the solid surface.
A novel cavitation tube and a flow visualization cell allowed for studying homogeneous and heterogeneous nucleation by hydrodynamic cavitation in de-ionized (DI) water system, which showed the generation of micron size bubbles when the throat velocity exceeded 8 m/s. It was found that the increase in fluid velocity slightly decreased bubble size, but increased the number of bubbles. Increasing the dissolved gas content led to the decrease in the on-set velocity for both homogeneous and heterogeneous nucleation. Additionally, it was verified that micron size bubbles were able to collide with and aggregate hydrophobic fine coal. The presence of micron size bubbles on the particle surfaces dramatically enhanced the conventional bubbles to attach to them. However, bubble aging was found to be detrimental to the bubble/particle attachment. Finally, it was found that heterogeneous nucleation only occurred on the crevices of the hydrophobic surfaces. -
- Subjects / Keywords
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- Graduation date
- Fall 2014
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- Type of Item
- Thesis
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- Degree
- Master of Science
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- License
- This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.