FLUIDIZED CRACKING CATALYST REGENERATION PROCESS AND APPARA- TUS

1528432 Regenerating catalyst TEXACO DEVELOPMENT CORP 21 Jan 1977 [7 May 1976 (2)] 02451/77 Headings B1E and B1F Coke-contaminated cracking catalyst is regenerated by flowing it via conduit 104 and open ended distributor into a first regeneration zone formed at the bottom of regenerator section 101 where it is intimately mixed with primary regeneration gas from gas conduit 106, the catalyst and gas then flowing into a second regenerator zone comprising a dense phase bed having a top surface 122, a temperature of 1050-1450‹C, a catalyst residence time of 3-20 minutes a specific coke burning rate of 0.05-1.0 1b coke/hour/1b catalyst and a regeneration gas superficial vapour velocity of 2.5-6.0 ft./sec, withdrawing hot regenerated catalyst from the bed via duct 128, flowing oxygen-depleted spent regeneration gas containing entrained catalyst from the bed into transition zone 102 where the reduction in upward velocity causes a major portion of entrained catalyst to fall back into the bed, and a dilute phase of entrained catalyst to be formed which flows into upper regeneration section 100, separating at cyclone 117a the dilute phase into flue gas and catalyst, the flue gas being discharged at 121 and the catalyst flowing down stand pipe 118 to the first regeneration zone.