Impact of a novel bitumen extraction process on mined oil sands tailings behavior

Abstract

Hybrid bitumen extraction (HBE) at ambient conditions has potential, as an alternative to the commercially used modified Clark hot water extraction (CHWE) for mined oil sands. In this work, the dewatering behaviors of tailings suspensions generated on a pilot scale from standard CHWE and from HBE are studied. Using a centrifuge-based technique, sediment height at a given centrifugal acceleration is measured as a function of time, as is equilibrium consolidation height vs. acceleration. By fitting the measurements to a consolidation model, compressive yield stress data is obtained. Settling of tailings suspensions under earth's gravitation are also observed for comparison. Results demonstrate that the suspensions from the pilot HBE process settle faster than those from standard aqueous process at a given acceleration. The data also suggest that the suspensions from the pilot HBE are more compressible, as indicated by higher final compressed solids weight fraction for a given yield stress.© 2018 Her Majesty the Queen in Right of CanadaAIChE Journal © 2018 American Institute of Chemical EngineersReproduced with the permission of the Minister of Natural Resources Canada. AIChE J, 65: 250–258, 2019.