Optimized Operation of Fluidized Catalytic Cracking Considering CO2 Fixation and Carbon Pricing

Recently, Japan and the European Union have been experiencing declining petroleum demand owing to global initiatives aimed at reducing environmental impact by curtailing CO2 emissions. Consequently, alternative products and operational conditions should be developed to utilize the fluid catalytic cracking (FCC) unit. Using simulation software (Aspen Hysys), this study modeled a typical FCC unit and compared the simulation results with operational data to ensure reproducibility. Two new process models were developed to investigate two scenarios: (i) the slurry discharged from the FCC unit is utilized as a feedstock for the FCC process and (ii) the slurry and fraction obtained from the downstream absorber of the FCC unit are introduced into a delayed coker unit to facilitate carbon fixation. Within an optimum riser outlet temperature (ROT) of 520-530 degrees C, the yields of gasoline and liquefied petroleum gas increased up to 4%. For profit performance, although ROT of 535-545 degrees C yielded peak efficiency, the CO2 emissions increased by 70%. Thus, a ROT of 530-540 degrees C, coupled with a delayed coker unit, can maximize profitability. Furthermore, a correlation graph illustrated the relationship between CO2 emissions and profit for selecting optimal FCC operational conditions.

Automated summary

Japan and the European Union are facing declining petroleum demand due to global environmental initiatives. This study used simulation software to model and compare a typical fluid catalytic cracking (FCC) unit, aiming to develop alternative products and operational conditions. The results showed that using the slurry discharged from the FCC unit as a feedstock or introducing it into a delayed coker unit can increase yields and maximize profitability within specific temperature ranges.