Enhanced thickened tailings performance via additional chemical treatments

摘要

Many technologies are currently being advanced to treat oil sands tailings to improve deposition performance. This performance is greatly affected by feed variability and faces challenges of sand/fines segregation and liquefaction when the tailings are placed in thick lifts after deposition. Thickening technology, with its rapid density increase and water recovery of the tailings stream, resulting in non-segregated thickened tailings, is gaining more interest in the oil sands industry. However, thickened tailings do not reach the geotechnical requirements within current constraints, and this creates a driver for combining this technology with additional chemical treatments. This work presents laboratory and pilot-scale data of chemically treated thickened tailings, which indicate that chemical additions improve the floe structure, accelerate water release and sedimentation, and enhance strength gain and geotechnical properties.