Abstract: A company's 2.80 Mt/a MIP-CGP catalytic cracking unit serves as the primary production unit for refining structure adjustment. Since its startup, the unit has faced challenges such as intensified feedstock deterioration and frequent variations in feedstock properties. Meanwhile, it is required to reduce diesel production based on operational demands while increasing gasoline or liquefied gas (LPG) output, ensuring that gasoline olefin and benzene content meet quality standards. By implementing measures such as increasing the outlet temperature of the first reaction zone, raising the feed preheating temperature, optimizing the stripping steam flow rate, adjusting balancing agent activity and catalyst formulation, processing diesel and light cycle oil from the residue hydrotreating unit using the LTAG nozzle, and employing deep catalytic cracking additives, the combined yield of gasoline and LPG was stabilized at around 64%, significantly exceeding the design value. Diesel production was substantially reduced, and the research octane number of gasoline remained consistently above 92.5. Following optimization, the unit's annual economic benefit increased by about 105.38 million yuan.

Key words: catalytic cracking, SYC deep catalytic cracking additive, MIP-CGP process, diesel, gasoline