AM-02-58 ADVANCED FCC FEED PRETREATMENT TECHNOLOGY AND CATALYSTS IMPROVES FCC PROFITABILITY

Description:

FCC feed pretreatment is an excellent tool to meet required sulfur levels in gasoline. In addition it provides substantial economic benefits to the refiner by increasing the yields of high value FCC Unit products and lowering the yields of low value products. However, in order to meet the latest, most stringent gasoline sulfur specifications, the feed to FCC units will have to be desulfurized to a degree that will force existing FCC pretreaters to be operated at a very high severity (temperature). For some FCC pretreaters this will only be feasible by adding more catalyst (reactor) volume to the unit. Operating FCC pretreaters at such severe conditions will have a detrimental effect on polynuclear aromatics (PNA) saturation, thereby lowering the economic benefits of FCC feed pretreatment. Revamping existing FCC pretreaters by adding on the Topsøe Aroshift process will effectively reverse the negative effects of increased severity. Aroshift is a simple process comprising technology and specialty catalyst which will lower the sulfur and PNA content in the feed to the FCC unit. The Aroshift process increases FCC conversion, increases yields of gasoline and C3/C4 olefins, and reduces the amount of LCO and HCO. Moreover, the quality of the FCC gasoline is improved. In this presentation, a comparison is presented for FCC pretreatment with and without Aroshift. The pretreated FCC feeds were tested in an FCC pilot plant, and the various products were measured and analysed. For both types of operation published values and costs are combined with cost estimates to calculate the rate of return for the Aroshift process.