Mechanistic Model for One-Dimensional Consolidation Behavior of Nonsegregating Oil Sands Tailings

Abstract

Thermal-chemical-hydraulic separation process is used to extract bitumen from surface mined oil sands ores. Huge amounts of oil sands fine tailings are produced from the extraction process. The most fundamentally challenging issue facing the geo-environmental community is containment, long-term storage, and volume reduction of oil sands fine tailings. One of the fine tailings disposal techniques is to homogenize fine tailings with coarse tailings forming nonsegregating tailings (NST). NST exhibits enhanced performance in consolidation and strength, and reduction in water retention as compared to fine tailings. This paper examines one-dimensional consolidation behavior of NST with varying fine and coarse tailings compositions. A mechanistic model based on theory of mixture is developed and proposed to predict consolidation behavior of NST. This model is demonstrated to achieve an optimum design of NST for accelerated consolidation rate and water recovery.