Fluid cat cracking heavy using stripped catalyst for feed preheat and regenerator temperature control

摘要

A fluid cat cracking process for catalytically cracking a feed containing vanadium into lower boiling products, includes a cat cracker and a regenerator, with the feed entering the catalytic cracking zone preheated by indirect heat exchange with spent, stripped catalyst particles being recycled from the cracking reactor to the regenerator. Operating the regenerator at a temperature no higher than about 1150. degree. F. permits the amount of vanadium in the feed to be substantially increased with no loss of catalytic activity due to vanadium poisoning of the catalyst, when compared to a higher regenerator temperature of 1365. degree. F. Using the stripped, spent catalyst for heating the feed reduces feed coking and heat exchanger fouling, compared to using the hotter regenerated catalyst for feed preheat.