Desiccation and Consolidation in Centrifuge Cake Oil Sands Tailings

Amongst available technologies to the oil sands mining industry for processing fluid fine tailings, centrifuge treatment technology has had some success at larger scales. In order to study coupled evaporation-consolidation behavior of centrifuged tailings in some detail, a multilayer "dry box" deposition test was performed. Centrifuge oil sands tailings were deposited in a "dry box" setup, and allowed to dry while measuring solid content, suction, and drainage history. Furthermore, the analysis of crack development was used to further assess their dewatering behavior. The influence of cracking on evaporation appears to be minimal. While evaporation rates remained near the potential rate for most of the tests, an eventual decline in evaporation rate appears to arise from high osmotic suctions generated by propagation of dissolved mass to the surface. In terms of dewatering optimization, results suggest that thin-lift deposition is somewhat more advantageous than thick-lift deposition. (Full abstract in thesis).