Abstract:
Methods for drying oil sand fine tailings treated to comprise flocculated fine tailings, by deposition and farming techniques, are provided. A deposition cell is provided with a sloped bottom surface and the flocculated fine tailings are deposited to undergo channelless advancement in the cell while allowing drainage of release water. When the deposit is uneven, the deposit may be plowed while wet for spreading and ensuring water release conditioning is imparted thereto, while avoiding over-shearing, and maintaining sufficient shear strength to allow standing. Once a dried upper crust forms, the deposit may be harrowed to break up the crust, expose wet regions there-beneath and create furrows in the standing deposit. The methods improve the dewatering and drying of mature fine tailings in oil sands.
Abstract:
A process for dewatering oil sand fine tailings is provided and comprises a dispersion and floc build-up stage comprising in-line addition of a flocculent solution comprising an effective amount of flocculation reagent into a flow of the oil sand fine tailings; a gel stage wherein flocculated oil sand fine tailings is transported in-line and subjected to shear conditioning; a floc breakdown and water release stage wherein the flocculated oil sand fine tailings releases water and decreases in yield shear stress, while avoiding an oversheared zone; depositing the flocculated oil sand fine tailings onto a deposition area to form a deposit and to enable the release water to flow away from the deposit, preferably done in a pipeline reactor and managing shear according to yield stress and CST information and achieves enhanced dewatering.
Abstract:
Methods for drying oil sand fine tailings treated to comprise flocculated fine tailings, by deposition and farming techniques, are provided. A deposition cell is provided with a sloped bottom surface and the flocculated fine tailings are deposited to undergo channelless advancement in the cell while allowing drainage of release water. When the deposit is uneven, the deposit may be plowed while wet for spreading and ensuring water release conditioning is imparted thereto, while avoiding over-shearing, and maintaining sufficient shear strength to allow standing. Once a dried upper crust forms, the deposit may be harrowed to break up the crust, expose wet regions there-beneath and create furrows in the standing deposit. The methods improve the dewatering and drying of mature fine tailings in oil sands.
Abstract:
A process for dewatering oil sand fine tailings is provided and comprises a dispersion and floc build-up stage comprising in-line addition of a flocculent solution comprising an effective amount of flocculation reagent into a flow of the oil sand fine tailings; a gel stage wherein flocculated oil sand fine tailings is transported in-line and subjected to shear conditioning; a floc breakdown and water release stage wherein the flocculated oil sand fine tailings releases water and decreases in yield shear stress, while avoiding an oversheared zone; depositing the flocculated oil sand fine tailings onto a deposition area to form a deposit and to enable the release water to flow away from the deposit, preferably done in a pipeline reactor and managing shear according to yield stress and CST information and achieves enhanced dewatering.