Method and system for treating catalytic cracking reaction product and use thereof

A method for treating a catalytic cracking product, comprising the steps of:

• feeding a first feed into a catalytic cracking reactor for catalytic cracking reaction in presence of a catalytic cracking catalyst to produce the catalytic cracking product;
• carrying out a first fractionation on the catalytic cracking product to obtain a heavy gasoline and a light gasoline, wherein the light gasoline has an initial boiling point of about 20-40° C. and a final boiling point of about 80-100° C., the heavy gasoline has an initial boiling point of about 80-100° C. and a final boiling point of about 200-250° C.;
• carrying out a second fractionation on a second feed to obtain a heavy fraction of gasoline and a middle fraction of gasoline, wherein the middle fraction of gasoline comprises C6-C8 light aromatics, has an initial boiling point of about 80-100° C., and a final boiling point of about 120-150° C., and the heavy fraction of gasoline comprises C9+ aromatics, has an initial boiling point of about 120-150° C., and a final boiling point of about 200-250° C.;
• carrying out an aromatics extraction on the middle fraction of gasoline to obtain BTX aromatics and an aromatic raffinate oil;
• sending the heavy fraction of gasoline to a fluidized reactor for dealkylation in the presence of hydrogen and a dealkylation catalyst to obtain a dealkylated liquid product and a spent dealkylation catalyst;
• and
• wherein the first feed comprises a hydrocarbon-containing feedstock oil, the light gasoline and the aromatic raffinate oil, and
• wherein the second feed comprises the heavy gasoline and the dealkylated liquid product,
• wherein the catalytic cracking product comprises a catalytic cracking oil gas, and a catalytic cracking gasoline.