Patent ID: 6045690
Filing Date: 2000-04-04
Classification: C10G

Abstract:
A process for the fluid catalytic cracking of heavy fraction oils, which comprises the steps of:a) feeding the heavy fraction oils to a raw oil introducing inlet provided at a downflow reaction zone inlet to bring the heavy fraction oils into contact with a regenerated catalyst, with the catalytic cracking being carried out under conditions of a contact time of 0.1 to 3.0 sec, a reaction zone outlet temperature of 530 to 700.degree. C. and a catalyst/oil ratio of 10 to 50 wt/wt to obtain a mixture of cracked product, unreacted material and spent catalyst;b) feeding the mixture of cracked product, unreacted material and scent catalyst into a separation zone and separating spent catalyst from the mixture;c) feeding spent catalyst separated from the mixture in the separation zone into a catalyst-stripping zone to remove hydrocarbons from the catalyst;d) feeding spent catalyst taken out of the catalyst-stripping zone into a catalyst-regenerating zone to remove the carbonaceous material and hydrocarbons deposited on the spent catalyst thereby obtaining the regenerated catalyst;e) feeding a part of the regenerated catalyst taken out of the catalyst-regenerating zone into a catalyst introducing inlet provided at the reaction zone inlet; andf) feeding another part of the regenerated catalyst taken out of the catalyst-regenerating zone into one to five intermediate catalyst introducing inlets which are provided between the catalyst introducing inlet provided at the reaction zone inlet and a reaction zone outlet.