Abstract: Under the backdrop of fluctuating market demand for low-sulfur marine fuel oil, gasoline, diesel, and petrochemical products, this study addresses the challenge of aligning production output with dynamic market shifts. Leveraging the core principles of the MFP technology, operational parameters and catalyst coupling strategies were systematically optimized in a 1.40 Mt/a heavy oil fluid catalytic cracking unit, enabling flexible product slate adjustment among marine fuel oil blending components, light olefins, and gasoline.Industrial results under the fuel oil blending mode, compared to the baseline case, demonstrate the following key performance indicators:Dry gas yield increased marginally from 2.83% to 3.38%;Total liquefied petroleum gas (LPG) yield rose from 21.00% to 26.13%, representing a 24.43% increase;Propylene yield increased from 6.16% to 9.30%, a 50.97% improvement;Isobutylene yield rose from 1.45% to 3.63%, a 150.34% enhancement;Fuel oil component yield increased from 21.69% to 29.54%, with no external discharge of oil slurry;Coke yield decreased from 8.41% to 7.15%, a 14.98% reduction, serving as one of the key pathways for the refining industry to achieve green and low-carbon transformation.From 2021 to 2023, the adaptive production strategy enabled by MFP technology significantly enhanced the plants responsiveness to market dynamics. The refining profit per ton of oil processed improved markedly—from 15.85 Yuan/t in 2019 to 279.49 Yuan/t in 2021, 219.09 Yuan/t in 2022, and 133.59 Yuan/t in 2023.

Key words: low-sulfur marine fuel oil, gasoline and diesel, light olefins, fuel oil components, flexible adjustment