Patent ID: 6517706
Filing Date: 2003-02-11
Classification: C10G

Abstract:
A process for hydrocracking a heavy hydrocarbon oil which comprises passing (a) a slurry feed comprising a mixture of a heavy hydrocarbon oil feedstock a substantial proportion of which boils above 524Â° C. and from about 0.01-4.0% by weight (based on fresh feedstock) of coke-inhibiting additive particles having an average size of less than about 30 &mgr;m and (b) a hydrogen-containing gas, upward through a confined hydrocracking zone in a vertical, elongated, cylindrical vessel with a dome-shaped bottom head, said hydrocracking zone being maintained at a temperature between about 350Â° C. and 600Â° C. and a pressure of at least 3.5 MPa and removing from the top of the hydrocracking zone a mixed effluent containing a gaseous phase comprisinghydrogen and vaporous hydrocarbons and a liquid phase comprising heavy hydrocarbons, wherein the slurry feed mixture and a portion of the hydrogen-containing gas are fed into the hydrocracking zone through a feed injector at the bottom of the dome-shaped bottom head and the balance of the hydrogen-containing gas is fed into the hydrocracking zone through a plurality of injection nozzles arranged within the hydrocracking zone at a location above the slurry-feed injector, with the temperature of the hydrogen-containing gas entering through the nozzles being at a temperature higher than the temperature of the combined slurry feed and hydrogen-containing gas entering through said bottom feed injector and the combined slurry feed and hydrogen-containing gas entering through the bottom feed injector at a velocity of at least 5 m/s whereby the additive particles are maintained in suspension throughout the vessel and coking reactions are prevented.