Abstract
A steady state model was developed for simulating the performance of an industrial fluid catalytic cracking (FCC) unit which was subsequently used in parametric sensitivity studies. The simulator includes kinetic models for the riser reactor and the regeneration systems. Mass and energy balances were performed for each of these sections and simulation results were compared with the plant data available in the literature. Model predictions were found to be in close agreement with the reported data. Finally this validated model was used for studying the effects of independent variables such as feed preheat temperature (Tfeed) and feed flow rate (Ffeed) on the unit performance at either fixed regenerated catalyst temp/regenerator temp (Trgn) or constant reactor outlet temperature (ROT). The catalyst circulation rate (CCR) was automatically adjusted to keep the ROT constant with varying the independent variables feed preheat temperature while the air rate adjusted for keeping the regenerator temperature constant which consequences the dependency of both dependent and independent variables on the unit performance. The air flow rate to the regenerator was also an independent variable during the parametric sensitivity analysis and its effect on FCC performance was investigated at constant Tfeed, Ffeed and CCR. Combining all the sensitivity analysis, it has been found to increase gas oil conversion and product yields by 5 to 6 percent with decrease of say, 10 K, in the feed preheat temperature (Tfeed) and corresponding increase in air rate (Fair) and catalyst circulation rate (Frgc) at constant reactor outlet temperature (ROT) and regenerated catalyst temperature (Trgc).
Highlights
Fluid Catalytic Cracking (FCC) is one of the most efficient secondary processes to increase gross refinery margin (GRM) and increase profitability as it converts low- priced heavy feedstock into lighter, more valuable hydrocarbons such as liquefied petroleum gas (LPG) and gasoline at high temperature and moderate pressure in presence of a finely divided silica/alumina based catalyst
A steady state model was developed for simulating the performance of an industrial fluid catalytic cracking (FCC) unit which was subsequently used in parametric sensitivity studies
The analysis showed that a decrease in feed preheat temperature by 10 K at fixed reactor outlet temperature (ROT) and fixed feed could possibly result in 4% increase in gas oil conversion and 3.9 % gasoline yield
Summary
Fluid Catalytic Cracking (FCC) is one of the most efficient secondary processes to increase gross refinery margin (GRM) and increase profitability as it converts low- priced heavy feedstock into lighter, more valuable hydrocarbons such as liquefied petroleum gas (LPG) and gasoline at high temperature and moderate pressure in presence of a finely divided silica/alumina based catalyst. One of the important advantages of fluid catalytic cracking is the ability of the catalyst to flow between the reactor and regenerator when fluidized with appropriate vapor phases Due to this fluidization of the catalyst, there is intimate interaction between the catalyst and hydrocarbons leading to more cracking reactions. The conversion and yield pattern strongly depend on the feedstock quality, operating conditions of the riser reactor-regenerator sections and the type of catalyst. These complex interactions coupled with economic importance of the unit have prompted many researchers to put their efforts on the modeling of this unit for better understanding and improved productivity. Many kinetic models have been developed using 2 - 6, 8, 10, and 12 lump schemes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
