Abstract: A grid of pipes for conducting steam at a pressure greater than a vessels' operating pressure and delivering the steam throughout the grid forms the internals for a tailings solvent recovery unit. The delivery of steam throughout the grid aids in maintaining a relatively low partial pressure throughout the vessel to act as a driver for mass transfer. Conducting the steam at the higher pressure through the pipes in the grid permits a surface of the pipes to be heated to a temperature higher than possible in a conventional vessel, increasing the heat transfer to the feed stream which flows through the grid.
Abstract: A system and method for managing fluid mature fine tailings (MFT) containment volume in a tailings pond to a minimum, fixed steady-state volume by balancing the accumulation of the MFT in the pond with consumption of the MFT from the pond by one or both of spiking the MFT into coarse sand tailings forming a coarse sand beach with trapped fines which is segregating for forming a trafficable deposit or centrifuging MFT from the tailings pond and depositing the resulting centrifuge cake on the coarse sand beach. During the life of the oil sand operation, when the volume of MFT approaches the fixed volume of the tailings pond, MFT is consumed from the pond using both sand-spiking and centrifugation as required. Production of MFT in the pond is also reduced by diverting an underflow from a secondary flotation cell in an extraction plant from the tailings pond to a thickener where the fines-rich thickened tailings from the thickener are beached for subsequent dewatering and reclamation.
Type:
Application
Filed:
April 4, 2011
Publication date:
October 4, 2012
Applicant:
TOTAL E&P CANADA LTD.
Inventors:
David BALDREY, Francis DEPARIS, Alexandre PACTAT, Pedro RIBEIRO, Bill SHAW, Alexander William HYNDMAN
Abstract: A tailings solvent recovery vessel substantially without conventional internals utilizes nozzles for forming very fine solvent-containing hydrocarbon droplets from a solvent-containing tailings feedstream. The hydrocarbon droplets are discrete from water droplets. The hydrocarbon droplets are small enough to result in a large surface area and a desired fall residence time but sufficiently large that they are not entrained with the rising vapor in the vessel. The feedstream is introduced to the vessel with a pressure drop to result in an initial flashing of the solvent from the solvent-containing droplets. Heat from the vessel atmosphere or from steam flowing countercurrent to the falling hydrocarbon droplets is transferred to the falling hydrocarbon droplets resulting in vaporization of any residual solvent therefrom. A substantially solvent-depleted pool is collected in the bottom of the vessel and retained only so long as is required to pump the underflow stream from the vessel.
Abstract: A tailings solvent recovery vessel substantially without conventional internals utilizes nozzles for forming very fine solvent-containing hydrocarbon droplets from a solvent-containing tailings feedstream. The hydrocarbon droplets are discrete from water droplets. The hydrocarbon droplets are small enough to result in a large surface area and a desired fall residence time but sufficiently large that they are not entrained with the rising vapour in the vessel. The feedstream is introduced to the vessel with a pressure drop to result in an initial flashing of the solvent from the solvent-containing droplets. Heat from the vessel atmosphere or from steam flowing countercurrent to the falling hydrocarbon droplets is transferred to the falling hydrocarbon droplets resulting in vaporization of any residual solvent therefrom. A substantially solvent-depleted pool is collected in the bottom of the vessel and retained only so long as is required to pump the underflow stream from the vessel.
Abstract: A tailings solvent recovery vessel substantially without conventional internals utilizes nozzles for forming very fine solvent-containing hydrocarbon droplets from a solvent-containing tailings feedstream. The hydrocarbon droplets are discrete from water droplets. The hydrocarbon droplets are small enough to result in a large surface area and a desired fall residence time but sufficiently large that they are not entrained with the rising vapour in the vessel. The feedstream is introduced to the vessel with a pressure drop to result in an initial flashing of the solvent from the solvent-containing droplets. Heat from the vessel atmosphere or from steam flowing countercurrent to the falling hydrocarbon droplets is transferred to the falling hydrocarbon droplets resulting in vaporization of any residual solvent therefrom. A substantially solvent-depleted pool is collected in the bottom of the vessel and retained only so long as is required to pump the underflow stream from the vessel.
Abstract: A process for treating bitumen froth with paraffinic solvent is provided which uses three stages of separation. Froth and a first solvent are directed to a first stage at a solvent/bitumen ratio for precipitating few or substantially no asphaltenes. A first stage underflow is directed to a second stage and a first stage overflow is directed to a third stage. A second stage underflow is directed to waste tailings and the second stage overflow joins the first stage overflow. A third stage underflow is recovered as an asphaltene by-product and a third stage overflow is recovered as a diluted bitumen product. At least a second solvent is added to one or both of the second or third stages for controlling a fraction of asphaltenes in the third stage underflow. Asphaltene loss to waste tailings is minimized and asphaltenes are now recovered as asphaltene by-product.