Research has shown that pump loop testing on oil sands thickened tailings (TT) samples can achieve a 50% reduction in yield stress with a centrifugal pump imparting about 2,500 kJ/m3 of mechanical energy. In commercial applications, transferring 2,500 kJ/m3 with centrifugal pumps requires recycle pump loops at the thickener underflow cone and multiple pumps in series. This increases the complexity and cost of a TT disposal system.A bench testing study by Goider in Peru has shown that the application of ultrasonic energy can shear-thin thickened tailings from base metal concentrators using the same order of magnitude energy input mentioned above. The samples tested had a solids content and rheology similar to that of oil sands TT. This indicates that ultrasonic energy may also shear-thin oil sands TT.This paper evaluates the potential applicability of ultrasonic shear thinning for oil sands TT. The benefits include being able to produce thickened tailings at higher solids contents (for faster consolidation after discharge) than what is currently targeted by the industry, decreasing the energy for pumping, and reducing uncertainty in pipeline design by employing simple and well-established rheology models.
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