摘要 |
NO-4-23531C/80 In a method of preventing bogging from occurring in the regeneration of a catalyst used in the cracking of heavy hydrocarbons, said catalyst containing iron oxides in an amount of about 30 to 60 wt% as Fe, wherein said catalyst in a fluidized bed, in the presence of coke deposited on the catalyst or said coke and an auxiliary fuel, is brought into contact with an oxygen-containing gas in an amount insufficient to achieve complete combustion of said coke or said coke and auxiliary fuel while simultaneously reducing the iron oxides in the catalyst, said method comprising holding the superficial velocity- (cm/sec) of said gas in the fluidized bed zone at a level of at least (0.112 t x temperature of fluidized bed(.degree.C) - 80.8). |