Modelling catalyst regeneration in an industrial FCC unit

Predictive models for process parameters during regeneration of spent catalyst in an industrial fluid catalytic cracking (FCC) unit are presented. The models adopt a twophase theory where the dense region of the regenerator is divided into a bubble-phase and an emulsion-phase. The bubble-phase is modelled as a plug flow reactor, while the emulsion-phase is modelled as a continuous stirred tank reactor (CSTR). Profiles for regenerator-temperature, quantity of coke burnt, and flue gas composition, at different operating conditions are also presented. Model-predictions are compared with plant data and good agreement is obtained. Simulation results indicate that inlet-air velocity and catalyst-bed height have significant influence on the performance of the rege nerator. The model-estimated optimum operating conditions of the regenerator are regeneratortemperature of about 1000 K, inlet-air velocity of about 13.5 m/s, and catalyst-bed height of 13 m.

[1]  J. R. Arthur.  Reactions between carbon and oxygen , 1951 .

[2]  H. de Lasa,et al.  Regeneration of cracking catalyst influence of the homogeneous CO postcombustion reaction , 1988 .

[3]  J. H. Handwerk,et al.  Petroleum Refining: Technology and Economics, Fifth Edition , 2007 .

[4]  A. Arbel,et al.  Dynamic and control of fluidized catalytic crackers. 1: Modeling of the current generation of FCC`s , 1995 .

[5]  David S. J. Jones,et al.  Handbook of petroleum processing , 2015 .

[6]  Paul N. Cheremisinoff,et al.  Hydrodynamics of gas-solids fluidization , 1984 .

[7]  Chang-Bock Chung,et al.  Dynamic modeling and simulation of a fluidized catalytic cracking process. Part I : Process modeling , 2001 .

[8]  A. Errazu,et al.  A fluidized bed catalytic cracking regenerator model , 1979 .

[9]  Reza Sadeghbeigi,et al.  Fluid Catalytic Cracking Handbook: An Expert Guide to the Practical Operation, Design, and Optimization of FCC Units , 2000 .

[10]  H. de Lasa,et al.  Analysis of fluidized bed catalytic cracking regenerator models in an industrial scale unit , 1981 .

[11]  J. Corriou,et al.  Modelling and Control of a Riser Type Fluid Catalytic Cracking (FCC) Unit , 1997 .

[12]  Patrick Leroy,et al.  FCC: Fluidization Phenomena and Technologies , 2000 .

[13]  J. Murthy,et al.  HYDRODYNAMICS OF GAS―SOLID FLUIDIZATION IN TAPERED BEDS , 2009 .

[14]  Yong Jin,et al.  Simulation of FCC catalyst regeneration in a riser regenerator , 1998 .

[15]  Raghunathan Rengaswamy,et al.  INDUSTRIAL EXPERIENCE WITH OBJECT-ORIENTED MODELLING FCC Case Study , 2004 .

[16]  Said S.E.H. Elnashaie,et al.  Digital simulation of industrial fluid catalytic cracking units—IV. Dynamic behaviour , 1993 .

[17]  H. de Lasa,et al.  On the determination of kinetic parameters for the regeneration of cracking catalyst , 1987 .

[18]  Wen-ching Yang.  Handbook of Fluidization and Fluid-Particle Systems , 2003 .

[19]  Jafar Sadeghzadeh Ahari,et al.  A MATHEMATICAL MODELING OF THE RISER REACTOR IN INDUSTRIAL FCC UNIT , 2008 .

[20]  Paul B. Weisz,et al.  Combustion of carbonaceous deposits within porous catalyst particles: II. Intrinsic burning rate , 1966 .

[21]  G. Froment,et al.  Chemical Reactor Analysis and Design , 1979 .