| 摘要 |
Cooling of stripped catalyst prior to regeneration in cracking process comprises (a) passing a mixture of catalyst and feedstock through a riser conversion zone under fluid catalytic cracking conditions to crack the feedstock; (b) passing the mixture, having a riser exit temperature, from the riser into a fluid catalytic cracking reactor vessel; (c) separating a portion of catalyst from the mixture, with the remainder of the mixture forming a reactor vessel gaseous stream; (d) heating the separated catalyst portion by combining it with a portion of regenerated catalyst to form combined catalyst; (e) stripping the combined catalyst, by contact with a stripping gas stream, comprising steam at a stripping temperature of 100 deg ((Dwg.0/1)) EPAB- EP-415935 B A process for controlling the fluid catalytic cracking of a feedstock containing hydrocarbons, comprising the steps of: passing a mixture comprising catalyst and the feedstock through a riser conversion zone under fluid catalytic cracking conditions to crack the feedstock; passing the mixture, having a riser exit temperature, from the riser into a fluid catalytic cracking reactor vessel; separating a portion of catalyst from the mixture, with the remainder of the mixture forming a reactor vessel gaseous stream; heating the separated catalyst portion by a heat step consisting essentially of combining the separated catalyst portion with a portion of regenerated catalyst from a fluid catalytic cracking regenerator vessel to form combined catalyst; stripping the combined catalyst, by contact with a stripping gas stream, at a stripping temperature between 55 deg.C above the riser exit temperature and 815 deg.C, the regenerated catalyst portion having a temperature between 55 deg.C above the stripping temperature and 871 deg.C prior to heating the separated catalyst to produce a stripped catalyst; cooling the stripped catalyst, prior to passing it into the regenerator vessel, to a temperature sufficient to cause the regenerator vessel to be maintained at a temperature between 55 deg.C above the stripping temperature and 871 deg.C wherein the cooling step comprises passing the stripped catalyst stream to a heat exchanger located outside the reactor vessel; and regenerating the cooled catalyst stream in the fluid catalytic cracking regenerator vessel by contact with an oxygen-containing stream at fluid catalytic regeneration conditions. (Dwg.0/1)
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