Oil Sands MFT Properties and Freeze-Thaw Effects

Abstract

This paper presents a framework for combining the chemistry and mineralogy of oil sands mature fine tailings (MFT) along with geotechnical knowledge of freeze-thaw processes, large strain consolidation and MFT behavior to develop a conceptual model incorporating the physicochemical processes associated with freeze-thaw dewatering. A conceptual model of freeze-thaw dewatering of oil sands MFT is proposed, which accounts for the release of water, change in mechanical and hydraulic properties, and alteration of the micro and macrofabric of MFT under one-dimensional conditions. Various solutions to the Neumann thermal model were examined to assess their ability to predict the rate of freezing and thawing of MFT. Models for predicting thaw and postthaw settlement were discussed as they pertain to freeze-thaw dewatering of MFT.