Patent ID: 7597794
Filing Date: 2009-10-06
Classification: C10C

Abstract:
1. A method for deep separation of a heavy oil with coupled post-extraction adjustable asphalt residue granulation, comprising the steps of: a) mixing, and feeding heavy oil feedstock and an extraction solvent into an extraction column, with a mass flow ratio of the extraction solvent and the heavy oil feedstock of 1.5 to 5.0:1; b) separating an asphalt-free oil phase from an asphalt phase in the extraction column by extraction, and discharging the asphalt-free oil phase from a top of the extraction column; c) introducing an additional amount of the extraction solvent to the asphalt phase in the extraction column, through a solvent inlet at a lower part of the extraction column, with a mass flow ratio of the extraction solvent and the heavy oil feedstock of approximately 0.2-2:1, and performing a further extraction of oil in the asphalt phase; d) discharging the asphalt phase, after completing the further extraction, out of the extraction column through an asphalt outlet at a bottom of the extraction column; e) adding a dispersing solvent consisting essentially of alkanes to discharged asphalt phase, through a dispersing solvent inlet of a gas-solid separator, at a mass flow ratio of the dispersing solvent to the asphalt phase of approximately 0.01-0.5:1 to form a dispersed asphalt phase, wherein an amount and condition of the dispersing solvent control asphalt granulation; f) carrying out gas-solid phase change separation on the dispersed asphalt phase in the gas-solid separator at a temperature above the boiling point of the dispersing solvent but below the softening point of asphalt, whereby the dispersing solvent becomes gaseous and the asphalt is dispersed into solid particles; formed solid asphalt particles having size thereof depending on the amount of the dispersing solvent added in step (e); and g) recovering vaporized dispersing solvent by condensation.