Patent ID: 9101854
Filing Date: 2015-08-11
Classification: B01D,B01J,C10G

Abstract:
1. An integrated hydrocracking and fluidized catalytic cracking process for conversion of a feedstock containing hydrocarbons having a boiling point greater than 300° C. into middle distillates and light olefins, propylene and butylene, the process comprising: a. introducing the feedstock and hydrogen into a first hydrocracking reaction zone containing a first hydrocracking catalyst to produce a first zone effluent; b. passing the first zone effluent and optionally additional hydrogen to a second hydrocracking reaction zone containing a second hydrocracking catalyst to produce a second zone effluent; c. passing the second zone effluent to a fractionating zone to produce at least a low boiling fraction and a high boiling fraction, and optionally one or more intermediate fractions; d. passing the high boiling fraction to a fluidized catalytic cracking reaction and separation zone, wherein the fluidized catalytic cracking reaction and separation zone operates under conditions that minimize olefin-consuming reactions and includes a fluidized catalytic cracking reactor that is in a downflow configuration and operates at a reaction temperature in the range of 580° C. to 630° C., a catalyst-to-oil ratio of 10:1 to 30:1, and with a contact time between catalyst particles and the bottoms fraction of about 0.1 seconds to about 1 second; e. recovering light olefins propylene and butylene from the fluidized catalytic cracking reaction and separation zone in a quantity of at least about 10 V % to about 20 V %, based on the volume of the initial feedstock; f. recovering middle distillate product from the fluidized catalytic cracking reaction and separation zone; and g. conveying at least a portion of remaining cycle oil from the fluidized catalytic cracking reaction and separation zone to the first and/or second hydrocracking reaction zone wherein the integrated process is operated to afford flexibility based on a desired product slate by varying the hydrocracking unit conversion efficiency in either or both of the first and second hydrocracking zones, wherein varying the hydrocracking unit conversion efficiency is by one or more of; operating with reduced efficiency catalyst in the first or second hydrocracking reaction zones to favor bottoms production and increase the quantity of feed to the fluidized catalytic cracking reactor thereby resulting in an increase in its products olefins and/or gasoline; or operating with a level of hydrogen feed that is relatively low to reduce the expense of hydrogen and increase the quantity of feed to the to the fluidized catalytic cracking reactor thereby resulting in an increase in its products olefins and/or gasoline.