Method for changing composition of catalytic cracking product

Abstract

The invention relates to a method for changing composition of a catalytic cracking product, and the method comprises the following steps: S1, selecting a running catalytic cracking system for producing gasoline and diesel oil, the system comprises a catalytic cracking reactor and a regenerator, and a catalytic cracking catalyst for producing gasoline and diesel oil circulates in the catalytic cracking reactor and the regenerator; s2, a transition catalyst is injected into the catalytic cracking system, continuous operation of catalytic cracking is kept, and a molecular sieve in the transition catalyst is composed of ZSM-5 molecular sieves; and S3, when the amount of the transition catalyst in the catalytic cracking system accounts for 30-40 wt% of the total storage amount of the catalyst in the system, injecting the catalytic cracking catalyst for producing low-carbon olefin into the system, and keeping continuous operation of catalytic cracking. According to the method, the problem that the yield of dry gas and coke is obviously increased in the rapid replacement process of the catalyst can be solved, and the yield of low-carbon olefin can be obviously increased.

Description

technical field [0001] The present application relates to petroleum refining and petrochemical processing, in particular to a method for changing the composition of catalytic cracking products. Background technique [0002] In August 2016, FCC waste catalyst was listed in the "National Hazardous Waste List". According to the national hazardous waste management requirements, the production, storage, transportation, and disposal of FCC waste catalyst will be regulated by the state, and the treatment cost will increase significantly. The spent catalyst of FCC is actually the unloading balancer of the catalytic cracking unit, which is not suitable for the production needs of its own unit. [0003] As the domestic refined oil market becomes saturated, many refineries will adjust their product structure, shifting from fuel-based to chemical-based. Among them, the composition of the catalyst for the catalytic cracking unit to produce gasoline and diesel as the target product is ve...

AI Technical Summary

Problems solved by technology

[0002] In August 2016, FCC waste catalyst was listed in the "National Hazardous Waste List". According to the national hazardous waste management requirements, the production, storage, transportation, and disposal of FCC waste catalyst will be regulated by the state, and the treatment cost will increase significantly.

This method will generate a large amount of hazardous waste, which is a burden on the environment, and the disposal of hazardous waste is also a considerable economic burden for the refinery.

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