US 12,134,737 B1
Fluid catalytic cracking unit with reactivity based naphtha recycle to enhance propylene production
Omer Refa Koseoglu, Dhahran (SA)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Apr. 20, 2023, as Appl. No. 18/303,998.
Int. Cl. C10G 11/00 (2006.01); C10G 11/18 (2006.01)
CPC C10G 11/187 (2013.01) [C10G 2300/1059 (2013.01); C10G 2300/107 (2013.01); C10G 2300/1074 (2013.01); C10G 2300/4018 (2013.01); C10G 2300/4081 (2013.01); C10G 2400/20 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A process for producing light olefins through fluidized catalytic cracking (FCC), the process comprising:
contacting a hydrocarbon feed with an FCC catalyst in an FCC reactor at reaction conditions that cause at least a portion of hydrocarbons from the hydrocarbon feed to undergo catalytic cracking reactions to produce a cracking effluent comprising the light olefins, where the light olefins comprise ethylene, propylene, butenes, or combinations of these, wherein the hydrocarbon feed comprises one or more heavy oils and has at least one of the following:
a boiling point at 50 wt. % of greater than or equal to 350° C.,
a Final Boiling Point of greater than or equal to 565° C., or
an API gravity of from 10 degrees to 50 degrees;
separating the cracking effluent in a cracking effluent separation system to produce a light olefin effluent and a plurality of FCC naphtha fractions, where:
the light olefin effluent comprises propylene, butenes, or combinations thereof,
each of the plurality of FCC naphtha fractions has a different boiling point temperature range; and
the constituents of all of the plurality of FCC naphtha fractions have a number of carbon atoms between 5 and 12;
recycling at least two of the FCC naphtha fractions back to the FCC reactor; and
injecting each of the FCC naphtha fractions at a different location within the FCC reactor based on reactivity of each of the at least two of the plurality of FCC naphtha fractions.