| This research investigates the evaporative behaviour of oil sands thickened tailings from a Pilot plant at the Total E&P operations in Alberta. The materials under study are of 50 and 55% solids concentration and have average sodium concentrations of 527 and 660 mg/L respectively.;Results indicate that high salinity shuts down evaporation due to the precipitation of salts on the surface causing an increase in total suction, while cracking facilitates drying through the exposure of underlying material with lower suctions. Additionally, multilayer tests show that the infiltration of water from new layers into desiccated underlying layers contributes to significant volume change and a more uniform drying of the tailings.;A series of small scale and medium scale drying tests were conducted in which mass loss through evaporation, crack propagation, total suction and solids concentrations were measured. Multilayer deposition was simulated and tailings were sectioned to analyse uniformity in drying and solute transport. |
