MULTI-STAGE COUNTER-CURRENT FROTH SETTLER AND METHOD OF USE

摘要

In a method for recovery of bitumen from a bitumen-containing froth, the froth is first diluted with solvent and the diluted froth is added to a single, froth settling vessel above a plurality of internals. Additional of the solvent is added to the vessel, either below the internals, intermediate the internals or both and is flowed counter-current to the diluted froth which is flowing downwardly over the plurality of internals. A gradient of solvent concentration relative to hydrocarbon concentration is formed through the internals which act as multiple stages of separation. Bitumen, solvent and other light components are produced at a top of the vessel. Heavier water, solids and asphaltene aggregates are recovered at the bottom of the vessel. For paraffinic solvents, the solvent to bitumen ratio of the dilution solvent is below an asphaltenes rejection ratio for isolating subsequent asphaltene rejection within the settling vessel.