Patent ID: 7641870

Claim:
An apparatus for cracking a hydrocarbon feedstock containing resid, said apparatus comprising: (1) a convection heater for heating said hydrocarbon feedstock; (2) an inlet for introducing steam to said heated hydrocarbon feedstock to form a mixture stream; (3) a flash/separation drum for treating said mixture stream to form i) a vapor phase which partially cracks and/or loses heat causing partial condensation of said vapor phase to provide supersaturated coke precursors as entrained liquid, and ii) a liquid phase; said drum further comprising a flash/separation drum overhead outlet for removing the vapor phase as overhead and a flash/separation drum liquid outlet for removing said liquid phase as bottoms from said flash/separation drum; (4) at least one device downstream of said overhead outlet for introducing to said overhead a hydrocarbon-containing nucleating liquid substantially free of resid and comprising components boiling at a temperature of at least about 260° C. (500° F.) under conditions sufficient to at least partially coalesce said coke precursors to provide residue coke precursor liquid; (5) a means for removing said coke precursor liquid from the treated overhead; (6) a convection heater for heating said treated overhead to provide a heated vapor phase; (7) a pyrolysis furnace for cracking the heated vapor phase to produce an effluent comprising olefins; and (8) a means for quenching the effluent and recovering cracked product therefrom.