Rational waste management for large mineral extraction operations requires behavioural information and a clear understanding of processes. The behaviour of the clay/water/bitumen/sand systems at Syncrude Canada Ltd. is being studied. The macroscopic behaviour is becoming well understood, particularly with respect to the role of bitumen. The bitumen aids settlement, but hinders consolidation. Clay mineral behaviour in the presence of bitumen is unclear and remains worthy of detailed study, particularly with respect to the nature of the mineral/bitumen interface in the presence of various ions.
Data are presented on system rheology, gel strength of sand/sludge mixes, the void ratio to permeability relationships for sludge, and the void ratio/effective stress relationship for sludge. Of considerable interest are the data at extremely low stresses, less than 1.0 kPa, as the great majority of water is expelled below this stress value.