Modelling of a Fluidized Catalytic Cracking Process

Computers & Chemical

Computers and Chemical Engineering 24 (2000) 168 1 - 1687 Engineering

www.elsevier.com/locate/compchemeng

Modeling of a fluidized catalytic cracking process

In-Su Han a, Chang-Bock Chung b,*, James B. Riggs a

a Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA b Faculty of Applied Chemistry, Chonnam National University, Kwangju 500-757, South Korea

Abstract

The purpose of this study is to develop a detailed dynamic model of a typical fluidized catalytic cracking (FCC) unit that consists of the reactor, regenerator, catalyst transport lines, and several auxiliary units (pre-heater, catalyst cooler, and blowers). Hydrodynamic descriptions for the crucial parts of the unit are incorporated into the model. Special attention has been paid to the reactor riser to predict the velocity distributions of the catalyst and gas phases, the molar concentrations of IO-lump species, and the temperature profile by utilizing momentum, mass, and energy balances. The regenerator is modeled in such detail that the two-regime (dense bed and freeboard), two-phase (emulsion and bubble) behavior of typical fluidized beds can be described. The models for cyclones, valves, and several auxiliary units of the FCC unit are also applied to investigate their dynamic effects on the overall system. The resulting model equations are grouped into 14 modules each of which corresponds to a specific part of the unit and type of equations, and then an efficient iterative scheme is employed for convergence of all the modules. The model solver is constructed on the basis of a modular approach and then implemented by a Fortran code. Finally, to validate the developed simulator, the steady-state simulation results are compared with those in the literature and the dynamic responses of the process are predicted and analyzed. 0 2000 Elsevier Science Ltd. All rights reserved.

Keywords: Fluidized catalytic cracking; Fluidized bed; Modeling; Regenerator; Riser; Sequential modular

1. Introduction

A fluidized catalytic cracking (FCC) process is a unit that converts heavy distillates like gas oils or residues to lighter petroleum fractions like gasolines or LPG using a cracking catalyst. Since a typical FCC unit can con- vert a large amount of feedstock into more valuable products, the overall economic benefits of a refinery could be considerably increased if proper control and optimization strategies are implemented. But, analysis and control of FCC processes have been known as challenging problems due to the following process characteristics, (1) very complicated and little known hydro- dynamics, (2) complex kinetics of both cracking and coke burning reactions, (3) strong interactions between the reactor and the regenerator, (4) many operating constraints.

* Corresponding author. Tel.: + 82-62-5301884; fax: + 82-62- 5301899.

E-mail address: [email protected] (C.-B. Chung).

Several studies on the dynamic modeling of the whole FCC unit have been presented in recent papers. Elnashaie and coworkers (Elnashaie & Elshishini, 1993) extended their steady-state model to a simple dynamic model, and investigated the sensitivity and stability of a bed-cracking type FCC unit. Mcfarlane, Reineman, Bartee and Georgakis (1993) presented a comprehen- sive model that covers most parts of a Model IV type FCC unit, including the reactor, regenerator, bowers, U-bends, compressors, furnace, and valves. The numer- ous empirical equations in the model are tailored to the Model IV FCC unit, making it difficult to extend to other types of FCC units. Arbel, Huang, Rinard, Shin- nar and Sapre (1995) developed a model that can describe both the steady-state and dynamic behavior of an FCC unit being operated in either the partial or full combustion modes.

The purpose of this study is to develop a detailed dynamic model of a modern riser-type FCC unit. The dynamic model is developed to complement the previous models presented in the literature and is expected to serve as a tool for various process system studies on FCC processes.

0098-1354/00/$ - see front matter 0 2000 Elsevier Science Ltd. All rights reserved. PII: SOO98-1354(00)00453-l

1682 I.-S. Han et al. /Computers and Chemical Engineering 24 (2000) 1681-1687

2. Process description

Fig. 1 shows a typical FCC process that consists of two major operating parts, the reactor riser and the regenerator. The cracking reaction of the hydrocarbon feed takes place in the riser, while the regenerator reactivates the catalyst by burning the coke deposited on the catalyst in the riser reactor. The feed is pre- heated to a temperature of 450-600 K in a furnace or in a pump-around from the main-fractionator. Then the feed is injected into the bottom of the riser along with a small amount of steam (OS-3 wt.% of feed), which leads to good atomization and reduces coke formation. The feed is subsequently vaporized upon contacting the hot catalyst flowing from the regenerator. The hydrocarbon vapors go through endothermic catalytic cracking reactions on their way up through the riser. Lighter hydrocarbons are produced as main cracking products along with by-product coke which deposits on the catalyst surface and lowers the catalyst activity. The residence time of the catalyst and hydrocarbon vapors in the riser is typically in the range 2-5 s. The riser top temperature is typically between 750 and 820 K and is usually controlled by regulating the flow of hot regenerated catalyst to the riser. The disengaging section of a modern riser-type reactor only serves to separate catalyst particles from vapors. The

Fresh

@ Waste heat boiler

a Disenppr a stripper 0 Riser

Flue gas

@ Catalyst cooler

eJ Air heater

@ Expander ‘3 Blower

@ Motor

Fig. 1. Schematic diagram of a typical FCC unit.

product vapor from the disengaging section enters a main-fractionator where vapor products are separated into various boiling point fractions. The spent catalyst is separated from the vapor in the reactor cyclone and falls into the stripping section where the hydrocarbons remaining on the surface are removed by stripping steam. The stripped spent ca’talyst is recycled through a catalyst transport line to the regenerator.

In the regenerator which is operated in the fluidization regime, the coke is burnt off the catalyst surface by the air blown into the bed. This combustion reaction serves to reactivate the catalyst and to maintain the bed temperature (950-980 K for a gas oil cracker, 980-1080 K for a resid cracker) high enough to sup- ply the heat required for the vaporization and cracking reactions of the feed in the reactor. The regenerated catalyst flows continuously into the riser bottom through another catalyst transport line. Resid cracking units are commonly equipped with one or more catalyst coolers to remove excess heat generated by burning a large amount of coke on the catalyst surface. Heat exchange takes place between the hot catalyst from the regenerator and the cooling water flowing through a bundle of tubes. The catalyst circulation rate between the reactor and the regenerator is controlled by the two slide valves installed in the catalyst transport lines.

3. Modeling

In this study, dynamic modeling is carried out for the reactor, regenerator, catalyst transfer lines, and several auxiliary units (feed pre-heater, catalyst cooler, and blowers) for a typical FCC unit. The reactor is dissected into the feed vaporization section, the riser, the disengaging-stripping section, and the reactor cyclones for modeling purposes. The regenerator is also broken into the dense bed, the freeboard, and the regenerator cyclones for modeling purposes. The following describes the modeling for each section or unit.

3.1. Feed vaporization section

The feed vaporizes when it is mixed with the regenerated catalyst in the feed vaporization section located at the bottom of the riser. The feed vaporization section is modeled as a macroscopic steady-state heat transfer system in which two streams (catalyst and feed) join. The temperature, pressure, and velocity of the vapor and the catalyst coming out of the vaporization section are calculated. These variables depend on the process variables such as feed temperature, feed characteristics, feed droplet size, catalyst temperature, and pressure. The volume expansion and temperature variation caused by the vaporization of liquid feed are

I.-S. Han et al. /Computers and Chemical Engineering 24 (2000) 1681-1687 1683

considered in the modeling of the feed vaporization section.

3.2. Reactor riser

The riser is modeled as a one-dimensional tubular reactor without radial and axial dispersion. Momen- tum, mass, and energy balance equations are derived for both the catalyst phase and the gas phase. The momentum equations are included in the riser modeling to describe the variations in the linear velocities of the catalyst and gas phases along the riser. There is signifi- cant molar expansion with increasing conversion of the feed and consequent acceleration of both the catalyst and gas phases (Theologos, Nikou, Lygeros & Markatos, 1997). Introducing the momentum equations can explain the molar expansion and catalyst slip in the riser and can considerably reduce the error arising from assuming constant values for such properties of the catalyst and gas phases velocities, volume fractions, density, and pressure. Furthermore, the momentum equations enable one to predict the pressure drop across the riser and consequently, the pressure in the feed vaporization section. The mass balance equations are used for predicting the component weight fractions of the lo-lumps (Jacob, Gross, Voltz & Weekman, 1976 Arbel et al. (1995)) the yields of the light gases (Ellis, Li & Riggs, 1998), and the coke on catalyst. The effect of catalyst deactivation due to catalytic coking, nitro- gen poisoning, and Conradson carbon is taken into consideration in the kinetic expressions. The catalyst temperature is higher than the gas temperature throughout the riser and the consequent heat transfer provides the heat required for the vaporization and endothermic reaction of the feedstock. The heat transfer between the two phases and the heat of cracking reaction are considered in the energy balance for the riser to predict the temperature of each phase.

3.3. Disengaging-stripping section

The disengager and the stripper of the reactor are combined into a single section called the ‘disengaging- stripping section’ in our model. The section is modeled as a perfectly-mixed continuous tank with no reaction taking place. Because the catalyst is immediately separated from the product vapor via the cyclones, further cracking reaction seldom occurs in the disengaging- stripping section. The disengaging-stripping model comprising the coke, catalyst, gas component, energy, and pressure balances is used to calculate several major state variables, the coke on catalyst after stripping, the catalyst and gas holdups, the concentrations of the gaseous component that flows to the main-fractionator, and the reactor temperature and pressures.

3.4. Reactor cyclones

Both the reactor and the regenerator of an FCC unit are usually equipped with several multi-stage cyclones to separate catalyst particles from entraining vapors. All the cyclones in the reactor are lumped into one modeling unit, which is then described as a continuous stirred tank (CST). Because no cracking reaction takes place in the reactor cyclones, the cyclones are in ther- mal equilibrium with the disengaging-stripping section. Therefore, only the mass balances are required to calculate the following state variables, the reactor cyclone inlet velocity; the catalyst holdup in the reactor cyclones; and the mass flow rate of the fluids exiting the reactor.

3.5. Overall regenerator

The total catalyst and gas holdups, superficial gas velocity, average gas density, and pressur& are calculated from the balances around the regenerator as a whole. These values are then used in the model equations for each section. The dynamics of the total catalyst and gas holdups are important in describing the interactions between the reactor and the regenerator because these variables strongly affect the catalyst flow rates between the two vessels. The pressures at the dense bed outlet and the bottom of the regenerator are calculated by applying average gas density and are, then, used to compute the flow rates through the catalyst transport lines.

3.4. Dense bed

In this study, the dense bed is modeled to consist of the emulsion and bubble phases on the basis of the two-phase theory of fluidization (Kunii & Levenspiel, 1991). The dynamic balances for the dense bed are based on a hybrid reactor model combining a mixed- tank reactor for coke and energy balances and a tubular reactor for gas component balances. It is assumed that the coke (CH,) burns in the dense bed according to the following reaction schemes (Weisz, 1966; Hano, Nakashio & Kusunoki, 1975):

CH, + (0.5 + 0.25q)O, + CO + 0.5qH20,

rl = kTR&&

CH, + (1 + 0.25q);, + CO2 + 0.5qH,O,

r2 = k%&ckCO (1)

Besides the coke burning reaction, combustion of carbon monoxide takes place. It may take place in the form of either homogeneous oxidation in the gas phase with the kinetics proposed by Howard, Williams and Fine (1973):

2co + 0, + 2co,, r3 = k,,GC,OC~~C$S, 2 ’ (2)


or heterogeneous oxidation in presence of the catalyst which contains small amounts of oxidation promoters like vanadium, nickel, or copper. Krishna and Parkin (1985) and Ali and Rohani (1997) reported the following kinetics for the heterogeneous oxidation:

catalyst

2co+o* + 2co,, r4 = k4R&-oC:5. 2

The hydraulic properties, such as the bed heights, phase volume fractions and velocities, represent the major modeling elements for the regenerator because they are closely connected to the mass and energy balances in the bed. But the detailed description of the hydraulics is quite involved due to the inherent complexity of the fluidization phenomena. From the gas component, coke, and energy balances, the following state variables are computed, the molar concentrations of gaseous substances along the axial position of the dense bed, the coke on catalyst, and the dense bed temperature. In addition, the volume fractions and the dense bed height are ca1ct.G lated from other mass balances and empirical expressions.

3.7. Freeboard

The freeboard is modeled as a tubular reactor. Em- ploying a freeboard model is important in predicting the after-burning reactions in the freeboard. The coke burning reaction in the freeboard also follows the reaction schemes described by Eqs. (l)-(3). In most models for the freeboard in the literature, the hydraulic properties such as the volume fraction of catalyst, is usually assumed to be constant along the freeboard. But, the concentration of the catalyst tends to decay exponentially with increasing height in the freeboard (Kunii & Levenspiel, 1991). The freeboard model, which is composed of the gas component, energy, and coke balances is used to calculate several state variables, the molar concentrations of gaseous substances, coke on catalyst, and the temperature along the axial position of the freeboard.

3.8. Regenerator cyclones

The regenerator cyclones are also modeled as a continuous stirred tank like the reactor cyclone. A pseudo-steady state is postulated because the catalyst residence time in the regenerator cyclone is much shorter than in other regenerator sections. The after- burning of CO to CO2 in the regenerator cyclones (including a plenum chamber) is likely to occur when there is an excess of both oxygen and carbon monoxide. In this study, the temperature rise across the regenerator cyclones is estimated using the simple correlation (Hovd & Skogestad, 1993). The regenera-

tor cyclone model yields the mass flow rate of the catalyst into the regenerator cyclones, the catalyst holdup in the regenerator cyclones, and the regenerator cyclone temperature.

3.9. Catalyst transport lines

The catalyst circulation rate between the reactor and the regenerator is controlled by the two slide valves installed in the catalyst transport lines. The catalyst circulation rate through each catalyst transport line is determined by the pressure drop across a slide valve. Because the catalyst residence time in the catalyst transport lines is in the order of a few sec- onds for stacked type FCC units and 10 s for the side-by-side type FCC units, it is possible to ignore the transport lag throughout the catalyst transport lines in the model. The catalyst transport line equations yield the mass flow rates through the spent and regenerated catalyst transport lines.

3.10. Feed pre-heater

The feed pre-heater is modeled as a furnace. It is assumed that the flame temperature in the combustion chamber does not vary with position and that the temperature of the air supplied to the pre-heater is equal to that of the surroundings. The feed pre- heater energy balance yields the temperature of the heating coil and the temperature of the combustion chamber of the furnace.

3.11. Catalyst cooler

Resid cracking units employ either internal bed coils or external heat exchangers as catalyst coolers to remove excess heat generated in the regenerator. The temperature in the catalyst bed of the catalyst cooler is assumed to be uniform because the air blown into the cooler fluidizes the catalyst. The following variables are calculated using the catalyst cooler equations, the temperature of the catalyst cooler bed and the temperature of the exiting steam.

3.12. Blowers and compressors

FCC units are equipped with air blowers and gas compressors, main air blower, catalyst cooler air blower, and wet gas compressor. Model equations for these gas-processing units take the same form as the model for a single-staged unit operated under an adi- abatic isentropic condition. The model equations are used to calculate the discharge temperatures of com- pressed gases.


Table 1 Major operating variables at the base steady-state

Flow rate of liquid feedstock Temperature of the liquid feedstock entering the

feed pre-heater

49.3 kg/s 302.0 K

Flow rate of the air entering the regenerator Catalyst circulation rate between the reactor and

the regenerator

35.0 kg/s 300.0 kg/s

Pressure at the main-fractionator Pressure at the stack gas discharge unit Ambient air temperature

101.0 kPa 110.0 kPa 300.5 K

4. Numerical algorithms

The entire collection of dynamic model equations for the FCC process represents a mixed system of differential (ordinary and partial) and algebraic equations and consists of a total of 217 equations. The model solver was developed on the basis of a modular approach in which the equations were grouped into the modules and then all the modules were sequentially solved by the iterative procedure employed in this study to obtain convergent solutions at every simulation time step. In this study the model equations are classified into 14 modules, each of which corresponds to a specific physical section of the reactor or regenerator and the type of equations.

Each individual module was solved using a solver specifically chosen for the type of equations in the module. There are four types of equations, and each type was solved by the following numerical methods: 1.

2.

3.

4.

Nonlinear algebraic equations. The HYBRDl routine of MINPACK (Garbow, Hillstrom & More, 1980) was used. It adopts the Powell’s hybrid algorithm based on a Newton’s method. Partial differential equations. The method of lines (MOL) was employed that converts the partial differential equation into a set of ordinary differential equations using finite difference approximation of the spatial derivatives and then integrates the set of equations with respect to time. First-order backward difference was used to approximate the con- vection terms. A non-uniform grid scheme was also adopted to enhance the flexibility of meshing. Coupled differential and algebraic equations. The Pezold-Gear’s BDF algorithm (Petzold, 1982) was used to solve the momentum equation of the reactor riser that belongs to this class of equations. The algorithm uses backward difference formulas and shows powerful performance for highly stiff problems. Ordinary differential equations. An LSODE routine (Hindmarsh, 1983) based on the GEAR’s algorithm was used. It implements a predictor-corrector method for non-stiff problems and a backward difference formula method for stiff problems. The rou-

tine was modified in this study to allow the concurrent integration of multiple modules.

The model and numerical algorithms developed in the previous section are implemented by a dynamic simulator which consists of a simulation engine and a user-friendly graphic interface. The simulation engine solves the model equations and is coded in Fortran 90 comprising approximately 12000 source lines in addition to package routines. The user-friendly graphic interface provides the user with graphical representa- tion of simulation results and is prepared by using MATLAB graphic tools.

5. Simulation examples

The dynamic simulator was used to investigate the behavior of a typical FCC unit capable of processing about 30 000 barrels of gas oil per day. Physical properties contained in our model were obtained from the various literatures and estimated using parameter esti- mation techniques on the basis of raw data in the literature (Technical Data Committee, 1988). The kinetic parameters of the lo-lump cracking reactions reported by Arbel et al. (1995) were applied to the simulations. The kinetic parameters for the oxidation of coke, homogeneous and catalytic oxidations of carbon monoxide were adopted from the papers of Morley and de Lasa (1988), Howard et al. (1973) and Ali and Rohani (1997), respectively. Major operating variables for the FCC unit at the base steady-state are listed in Table 1.

5.1. Steady -state results

A collection of steady state results was obtained by applying the dynamic simulator for a sufficiently long time until all the variables reached steady-state for each set of operating conditions to show the validity of our simulator by comparing our simulation results with those from the previous FCC models. Fig. 2 shows the steady state behavior of major state variables as func- tions of the air flow rate when the catalyst circulation rate is fixed at a specified value of 300 kg/s. Fig. 2a shows that with decreasing air flow rate the oxygen concentration gradually decreases until almost all the oxygen is exhausted. In this transition, the system moves from a so-called full-combustion mode to a partial-combustion mode (Arbel et al., 1995). The point of transition in combustion mode can be easily located as the maximum point of the curves for the regenerator or reactor temperature in Fig. 2a. Alternatively, this point corresponds to either the maximum point of the feed oil conversion or the minimum point of the coke on catalyst in Fig. 2c. The results shown in Fig. 2


exhibit good matches with the field observations and simulation results of Arbel et al. (1995) not only in terms of qualitative trend but also in terms of the slopes of the curves. The steady state behavior of the regenerator temperature shown in Fig. 2b is also analogous to that of Kumar, Chadha, Gupta and Sharma (1995).

5.2. Dynamic responses

Dynamic simulation of the FCC process was per- formed for a duration of 450 min, starting from the base steady-state in a partial combustion mode. The air flow rate is incrementally increased to 38, 41, and 44 kg/s at the simulation time equal to 0, 150, and 300 min, respectively, while the catalyst circulation rate is fixed at a specified value of 300 kg/s. Simulated responses of the system show quite different trends as shown in Fig. 3 depending on the combustion mode

1100

P

g 1050

z ;

P 2 1000

; H ; 2 950

%

1200

ii 1000 E

?L E

900 d

s

H 900 d

900 - 700

8, ,3

w

0

25 30 35 40 45 50

Air flow rate (kg/s)

Fig. 2. Steady-state responses to changes in air flow rate.

09 -I

Gas&e yield E

- o.ooo43

E

30 1 ‘0

0 100 200 3w 400

Time (min)

Fig. 3. Dynamic responses to changes in air flow rate.

characterized by the air flow rate. When the air flow rate is increased to 44 kg/s at 300 min, the system moves from the partial-combustion mode to the full- combustion mode.

When the system is operated in the partial combustion mode, increasing the air flow accelerates coke burning in the regenerator and, thus, raises temperature in every part of the unit (Fig. 3a) and reduces the CO concentration in the stack gas (Fig. 3b). The conversion of feed oil increases due to the elevated riser temperature and cleaner regenerator catalyst (Fig. 3~). As the operating mode of the system shifts to full combustion, however, this trend begins to be reversed. Since increasing the air flow rate has little effect on coke burning in the full combustion mode (Fig. 3c), there is a sharp increase in oxygen concentration in the stack gas (Fig. 3b). Consequently, both the reactor and regenerator temperatures start decreasing (Fig. 3a), and thus, cause the conversion of feed oil to decrease (Fig. 3~).


6. Conclusions

A detailed dynamic model for the reactor, regenerator, catalyst transport lines, and other auxiliary units of a modern riser-type FCC unit was developed on the basis of the conservation principles. The dynamic model was implemented using a Fortran code and the simulator was validated by comparing the overall steady state behavior of the system with those in the literature. Then, the dynamic responses of the system were simulated both in full- and partial-combustion modes. The dynamic model developed in this study is expected to serve as a valuable tool for various process system studies on FCC processes.

References

Ali, H., & Rohani, S. (1997). Dynamic modeling and simulation of a riser-type fluid catalytic cracking unit. Chemical Engineering Technology, 20, 118-130.

Arbel, A., Huang, Z., Rinard, I. R., Shinnar, R., & Sapre, A. V. (1995). Dynamic and control of fluidized catalytic crackers-l. Modeling of the current generation of FCC’s, Industrial Engi- neering and Chemical Research, 34, 1228-1243.

Ellis, R. C., Li, X., & Riggs, J. B. (1998). Modeling and optimization of a model IV fluidized catalytic cracking unit. American Institute of Chemical Engineering Journal, 44, 2068-2079.

Elnashaie, S. S. E. H., & Elshishini, S. S. (1993). Digital simulation of industrial fluid catalytic cracking units-IV. Dynamic behavior. Chemical Engineering Science, 48, 567-583.

Garbow, B. S., Hillstrom, K. E., & More, J. J. (1980). MINPACK Project, Argonne Nat. Lab.

Kunii, D., & Levenspiel, 0. (1991). Fluidization engineering (2nd ed.). Boston: Butterworth-Heinemann.

Mcfarlane, R. C., Reineman, R. C., Bartee, J. F., & Georgakis, C. (1993). Dynamic simulator for a model IV fluid catalytic cracking unit. Computers & Chemical Engineering, 17, 275-300.

Morley, K., & de Lasa, H. I. (1988). Regeneration of cracking catalyst influence of the homogeneous CO postcombustion reaction. Canadian Journal of Chemical Engineering, 66, 428-432.

Petzold, L. R. (1982). A description of DASSL: a differentiahalge- braic system solver. Sandia technical report. (pp. 82-8637).

Technical Data Committee, (1988). Technical data book-petroleum refining. American Petroleum Institute.

Theologos, L. N., Nikou, I. D., Lygeros, A. I., & Markatos, N. C. (1997). Simulation and design of fluid catalystic-cracking riser- type reactors. American Institute of Chemical Engineering Jour- nal, 43, 486-494.

Hano, T., Nakashio, F., & Kusunoki, K. (1975). The burning rate Weisz, P. B. (1966). Combustion of carbonaceous deposits within of coke deposited on zeolite catalyst. Journal of Chemical Engi- porous catalyst particles: III. The CO&O product ratio. Jour- neering Japan, 8, 127-130. nal of Catalysis, 6, 425-430.

Hindmarsh, A. C. (1983). ODEPACK: a systematized collection of ODE solvers. In R. S. Stepleman, Scientific computing. Amster- dam: North Holland.

Hovd, M., & Skogestad, S. (1993). Procedure for regulatory control structure selection with application to the FCC process. American Institute of Chemical Engineering Journal, 39, 1938- 1953.

Howard, J. B., Williams, G. C., & Fine, D. H., (1973). Kinetics of carbon monoxide oxidation in post flame gases. 14th Sympo- sium on internal combustion, Combustion Institiute, (pp. 915- 986).

Jacob, S. M., Gross, B., Voltz, S. E., & Weekman, V. M. (1976). A lumping and reaction scheme for catalytic cracking. American Institute of Chemical Engineering Journal, 22, 701-713.

Krishna, A. S., & Parkin, E. S. (1985). Modeling the regenerator in commercial fluid catalytic cracking units. Chemical Engineering Progress, 81, 57-62.

Kumar, S., Chadha, A., Gupta, R., & Sharma, R. (1995). CATCRACK: a process simulator for an integrated FCC-regenerator system. Industrial Engineering & Chemical Research, 34, 3737-3748.

Modelling of a Fluidized Catalytic Cracking Process

Documents

Transcript of Modelling of a Fluidized Catalytic Cracking Process