Patent ID: 7867321
Filing Date: 2011-01-11
Classification: C10G

Abstract:
1. A process for disengaging solid particles and gaseous product in a process for fluid catalytic cracking (FCC) of hydrocarbons, which reduces coke formation in a disengager vessel, by using a cyclone system for disengaging solid particles and gaseous product which is in association with a FCC reactor and which reduces coke formation in a disengager vessel that receives a catalyst/load mixture from a riser, comprising at least one legless cyclone connected to at least one cyclone in consecutive stages through concentric pipes, wherein the at least one legless cyclone is fitted with at least one collector pipe outside the at least one legless cyclone, the process comprising the steps of: a) feeding a suspension made up of cracking reaction products mixed with a catalyst in the cyclone disengaging system for fostering the disengaging of gaseous and particulate phases, with a gaseous current flowing into a fractionation system through an outlet duct; b) collecting a particulate phase in the bottom of the disengager vessel, from where it flows to a rectification and regeneration zone; c) purging stagnated areas of the disengager vessel by injecting purge liquid through an injector device; and d) draining off hydrocarbons recovered in a rectifier and steam injected into the disengager vessel and the rectifier, wherein, in step d), gases coming from the disengager vessel are drained off through the at least one collector pipe outside the at least one legless cyclone, avoiding the passage of hydrocarbons into the top of the disengager vessel, which has a lower temperature, and in step b), a minimum of the catalyst disengaged through a lower nozzle of the at least one legless cyclone is released by the gases drained off through the at least one collector pipe.