Pumping Oil Sand Froth

Froth is the basis to the extraction of bitumen from oil sand. Its components include sand, bitumen, water, and air. The technology of extraction and processing is evolving toward lower temperature of operation where the volumetric content of air and viscosity of bitumen challenge pumping. To improve the efficiency of froth handling pumps it is important to adapt the technology from other industries. This may include degassing while pumping with secondary vacuum impellers (expellers), recirculating a part of the slurry to the suction, or injecting external hot water. In an effort to reduce air locking problems and derating of performance, a special impeller for centrifugal pumps was developed. The impellers feature split vanes between the principal vanes. The design allows for adequate passageway for solids at the eye while reducing the formation of large pockets of air between the main vanes. Adequate vane thickness for principal and split vanes is maintained in this design to resist wear from sand.