Effect of Salinity on the Warm Water-Based Processing of Mineable Oil Sands

• Author / Creator

  Chen, Tong

• Due to the extensive usage of caustics and increased level of water recycling, the inevitable increase in salinity of recycle process water is a growing challenge in the current water-based bitumen extraction process. The present work concerns about how salinity affects bitumen recovery from various oil sands ores. Laboratory flotation results demonstrate that the decrease in bitumen recovery and froth quality by increasing the salinity of process water at pH 8.5 was ore-dependent. Increasing the salinity of process water caused a dramatic decrease in ore processability for the low-grade processing ores. In contrast, the increase in salinity up to 4000 ppm NaCl concentration in the process water showed a negligible effect on the processability of high-grade processing ores. Interestingly, the use of caustic to increase the pH of process water to 11.2 could not alleviate, but increase, the negative effect of salinity on the processability of low-grade ores.
  Systematic study was conducted to understand the significant effect of increasing salinity on bitumen recovery from poor processing ores. Using our refined in-situ bitumen liberation flow visualization cell, the salt addition was found to decrease the degree of bitumen liberation (DBL) from low-grade ores. At higher pH, the negative effect of salinity on the DBL was more evident. The zeta potential measurement revealed that the incremental zeta potential of fines and bitumen become less negative as the increase of salt concentration. The result from the induction time measurement also showed that increasing sodium concentration inhibits bitumen and bubble
  attachment in the presence of fines. The detrimental effect of salinity on bitumen aeration was more profound at higher pH of the process water. The results from this study aided to develop strategies of blending low-grade ore with high-grade ore, to minimize the negative impact of increased recycle water salinity on bitumen extraction.

• Subjects / Keywords

  • Oil
  • Salinity
  • Effect
  • Processing
  • Sands

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3G44J213

• 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.