Creep and structuration in centrifuge cake oil sands tailings

ABSTRACT: Operators in Alberta’s oil sands industry are required to improve the density and strength of existing tailings deposits to facilitate permanent reclamation to pre-existing boreal forest conditions. Several types of tailings deposits are envisaged and are either being attempted at commercial or pilot scales. One of these, deep deposits of fluid fine tailings (FFT) dewatered in centrifuge, may contain substantially deep (> 50 m) deposits that require substantial dewatering through consolidation. However, as the consolidation will take years to decades, time variant phenomenon such as creep and structuration may be important. This paper reports on preliminary experiments designed to investigate creep and structuration in centrifuge cake oil sands tailings. The experiment includes column dewatering tests with pore water pressure measurements, oedometer tests and fall cone tests. Preliminary results show similar behaviours reported for in-line flocculated FFT in previous studies