Patent ID: 6858128
Filing Date: 2005-02-22
Classification: C10G

Abstract:
1. A process for hydrocracking a hydrocarbonaceous feedstock which process comprises: (a) passing a hydrocarbonaceous feedstock, a liquid recycle stream and hydrogen to a hydrocracking zone containing hydrocracking catalyst; (b) partially condensing the effluent from said hydrocracking zone to produce a hydrogen-rich gaseous stream and a first liquid hydrocarbonaceous stream; (c) introducing at least a portion of said first liquid hydrocarbonaceous stream comprising hydrocarbons boiling at a temperature below the boiling range of said hydrocarbonaceous feedstock, hydrocarbons boiling at a temperature in the boiling range of said hydrocarbonaceous feedstock and heavy polynuclear aromatic compounds into a first zone of a divided-wall fractionation zone to produce at least one liquid hydrocarbonaceous product stream and a second liquid hydrocarbonaceous stream comprising hydrocarbons boiling at a temperature in the boiling range of said hydrocarbonaceous feedstock and heavy polynuclear aromatic compounds; (d) reintroducing at least a portion of said second liquid hydrocarbonaceous stream into a second zone located in the bottom end of said divided-wall fractionation zone to produce a third hydrocarbonaceous stream rich in polynuclear aromatic compounds; (e) recycling at least another portion of said second liquid hydrocarbonaceous stream to said hydrocracking zone to provide at least a portion of said liquid recycle stream; and (f) recovering said liquid hydrocarbonaceous product stream.