Effect of Residual Bitumen on Polymer-assisted Flocculation of Fluid Fine Tailings

  • Author / Creator
    Klein, Colin G
  • In bitumen recovery from oil sands, a percentage of the bitumen is lost to tailings. The effect of fugitive bitumen on fines settling and consolidation in tailings ponds remains controversial. In the current study, the settling performance of mature fine tailings (MFT) in response to flocculant addition was considered by studying MFT of varying bitumen content. Bitumen content in the MFT was adjusted by controlled removal of bitumen using a Denver flotation cell. The initial settling rate of flocculated MFT was observed to increase with decreasing bitumen content from 0.45 to 0.18 wt%. A further reduction in bitumen content was found to dramatically decrease the settling rate of flocculated MFT. Such behaviour seems counterintuitive since the polymer flocculant was found to have a low affinity for bitumen contaminated surfaces, as measured by quartz crystal microbalance with dissipation (QCM‐D), which would predict a further increase in settling rate of flocculated MFT with decreasing bitumen content. Reasons for this behavior were investigated and it was observed that the decrease in settling rate coincided with long periods of intense mixing in the Denver cell. The underlying reason for this behavior is the subject of ongoing investigation. The current study confirms the use of flotation as a viable option to control MFT bitumen content and improve the settling rate of flocculated MFT.

  • Subjects / Keywords
  • Graduation date
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • 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.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
    • Department of Chemical and Materials Engineering
  • Specialization
    • Chemical Engineering
  • Supervisor / co-supervisor and their department(s)
    • Xu, Zhenghe (Chemical and Materials Engineering)
  • Examining committee members and their departments
    • Xu, Zhenghe (Chemical and Materials Engineering)
    • Gupta, Rajender (Chemical and Materials Engineering)
    • Sanders, Sean (Chemical and Materials Engineering)