Patent ID: 6379533
Filing Date: 2002-04-30
Classification: C10G

Abstract:
A hydrocracking process for the simultaneous production of LPG and distillate hydrocarbons which process comprises the following steps:(a) passing a hydrocarbonaceous feedstock and hydrogen to a denitrification and desulfurization reaction zone at reaction zone conditions including a temperature from about 400Â° F. to about 900Â° F., a pressure from about 500 psig to about 2500 psig with a catalyst; and recovering a denitrification and desulfurization reaction zone effluent therefrom; (b) passing the denitrification and desulfurization reaction zone effluent directly to a hot, high pressure stripper utilizing a hot, hydrogen-rich stripping gas to produce a first vapor stream comprising hydrogen, hydrocarbonaceous compounds boiling at a temperature below the boiling range of the hydrocarbonaceous feedstock, hydrogen sulfide and ammonia, and a first liquid stream comprising hydrocarbonaceous compounds boiling in the range of the hydrocarbonaceous feedstock; (c) passing at least a portion of the first liquid stream comprising hydrocarbonaceous compounds boiling in the range of the hydrocarbonaceous feedstock to a first hydrocracking zone containing a first hydrocracking catalyst and operating at a temperature of about 400Â° F. to about 900Â° F. and a pressure from about 500 psig to about 2500 psig, and recovering a hydrocracking zone effluent therefrom; (d) passing the hydrocracking zone effluent in step (c) to the denitrification and desulfurization reaction zone; (e) condensing at least a portion of the first vapor stream recovered in step (b) to produce a second liquid stream comprising hydrocarbonaceous compounds boiling at a temperature below the boiling range of the hydrocarbonaceous feedstock and a second vapor stream comprising hydrogen and hydrogen sulfide in a high pressure separator; (f) recycling at least a portion of the second vapor stream to the first hydrocracking zone; (g) reacting at least a portion of the second liquid stream in a second hydrocracking zone containing a second hydrocracking catalyst to produce LPG boiling range hydrocarbonaceous compounds; (h) passing the resulting effluent from the second hydrocracking zone to the high pressure separator of step (e); and (i) separating at least another portion of the second liquid stream to produce a stream comprising LPG boiling range hydrocarbonaceous compounds and a stream comprising distillate hydrocarbons.