MULTI-PHASE AND CATALYTIC CHEMICAL REACTORS DESIGN SIMULATION TOOL

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MULTI-PHASE AND CATALYTIC CHEMICAL REACTORS
DESIGN SIMULATION TOOL

• Jack R. HopperJamal M. SalehSandeep
  WaghchoureSandesh C. HegdeNiraj
  RamachandranLamar University, Beaumont, TX
  77710Ralph W. PikeLouisiana State
  UniversityBaton Rouge, LA 70803

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Overview of Advanced Process Analysis System
Advanced Process Analysis System
On-Line Optimization
Process control
Process Modification
Reactor Analysis
Pinch Analysis
Pollution Index
Flowsheet Simulation
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OBJECTIVE
To develop a User Friendly Simulation Package for
multi-phase catalytic and non-catalytic reactor
analysis as a component for the Advanced On-line
Process Analysis System for Pollution Prevention
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REACAT REACTOR SIMULATION TOOL FEATURES

• User Friendly input/ output interface
• Graphical and Tabular Data Output
• Extensive Selection of Reactor Models
• Component Material Balances for Gas, Liquid and
  
• Catalyst Phase
• Total Energy Balance
• Prediction of reactor hydrodynamics such as
  
• pressure drop, power consumption, catalyst
  wetting
• factor and flow regimes
• Reactor Models with numerous Options

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Classification of Homogeneous and Heterogeneous
Reactor Models
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Reactor Definitions

• Catalytic Packed Bed Gas or Liquid Reactants
  flow over a fixed bed of catalysts.
• Catalytic Fluidized Bed The up-flow gas or
  liquid phase suspends the fine catalyst
  particles.
• CSTR Gas-Liquid Liquid and gas phases are
  mechanically agitated
• Bubble Gas-Liquid Bed Liquid phase is agitated
  by the bubble rise of the gas phase. Liquid phase
  is continuous.

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Reactor Definitions (Contd..)

• Trickle-Bed Concurrent down-flow of gas and
  liquid over a fixed-bed of catalyst. Liquid
  trickles down, while gas phase is continuous
• Bubble-Fixed Bed Concurrent up-flow of gas and
  liquid. Catalyst bed is completely immersed in a
  continuous liquid flow while gas rises as
  bubbles.
• CSTR Slurry Mechanically agitated
  gas-liquid-catalyst reactor. The Fine catalyst
  particles are suspended in the liquid phase by
  means of agitation. (Batch liquid phase may also
  be used)
• Bubble Slurry Column Liquid is agitated by means
  of the dispersed gas bubbles. Gas bubble provides
  the momentum to suspend the catalyst particles.
• Three-Phase Fluidized Bed Catalyst particles are
  fluidized by an upward liquid flow while gas
  phase rises in a dispersed bubble regime.

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Reactor Types Included in the Reactor Simulation
Tool, ReaCat
Homogeneous Reactors
Plug Flow
CSTR
Batch
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Reactor Types Included in the Reactor Simulation
Tool, ReaCat (Contd..)
Two-Phase Reactors
Gas /Liquid Catalytic Reactors
Fluidized Bed
Fixed Bed
Liquid
Gas-Liquid Reactors
Gas-Liquid Bubble Column
Liquid
Gas
Gas-Liquid CSTR
Gas
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Reactor Types Included in the Reactor Simulation
Tool, ReaCat (Contd..)
Three-Phase Reactors
Three Phase Catalytic Reactors
Liquid
Gas
Liquid
Liquid
Liquid
Gas
Gas
Gas
Cocurrent Downflow Trickle Bed
Cocurrent Upflow Packed Bed
Bubble Slurry Column
Three-Phase Fluidized Column
Liquid
Gas-Liquid Catalytic CSTR Slurry Reactor
Gas
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REACTION RATE MODEL OPTIONS

• Power-law reaction rate or Langmuir- Hinshelwood
  model to
  account for the adsorption effects.
• Correlations to estimate the external mass
  transfer effects and dispersion coefficients
• Catalytic effectiveness factor estimation to
  account for intra-particle resistance
• Flow Regime Options
• Isothermal and non-isothermal/non-adiabatic
  conditions
• Multi-reaction systems with up to 30 reactions
  and 36
• components

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Industrial Examples of Multi-phase and Catalytic
Reactors

• Catalytic Gas/ Liquid Fluidized-bed Reactor
• Fluid Catalytic
  Cracking
• Production of Allyl Chloride.
• Production of Phthalic Anhydride
• Acrilonitrile by the Sohio Process
• Catalytic Fixed Bed Reactor
• Partial oxidation of O-xylene to Pthalic
  Anhydride Hydrogenation of
  Aromatics and Olefins
• Dehydrogenation of Ethylbenzene to Styrene

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Industrial Examples of Multi-phase and Catalytic
Reactors

• Three-phase Reactor
• Trickle-Bed
• Catalytic hydro-desulfurization
• Catalytic hydrogenation
• Catalytic hydrocracking
• Fixed-bed upward bubble-flow
• Fischer-Tropsch
• Coal liquefaction
• CSTR Slurry
• Hydrogenation of fatty oils and unsaturated fats.
• Hydrogenation of acetone
• Bubble-Slurry Column
• Catalytic oxidation of olefin
• Liquid-phase xylene isomerization
• Three-phase fluidized Bed
• Production of calcium acid sulfite
• Coal liquefaction, SRC process

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Industrial Examples of Multi-phase and Catalytic
Reactors

• Gas-Liquid Continuous Stirred Tank Reactor
• Oxidation of cyclohexane to adipic acid, cumene
  to cumene
• hydroperoxide, and toluene to benzoic acid.
• Absorption of SO3 in H2SO4 for manufacture of
  Oleum
• Absorption of NO2 in water for the production of
  HNO3
• Addition of HBr to alpha olefins for the
  manufacture of alkyl
• bromide.
• Addition of HCl to vinyl acetylene for the
  manufacture of
• chlroprene.
• Absorption of butenes in sulfuric acid for
  conversion to
• secondary butanol.

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Multi-phase Reactors- Advantages and Disadvantages
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Multi-phase Reactors- Advantages and Disadvantages
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Three-phase Reactors- Advantages and Disadvantages
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Three -phase Reactors- Advantages and
Disadvantages
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Three -phase Reactors- Advantages and
Disadvantages
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Multi-phase Reactors- Advantages and Disadvantages
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Comparison of Three Phase Trickle- Bed and Bubble
Fixed Bed Reactors
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Comparison of Three Phase Suspended Bed Reactors
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Gas-Liquid-Solid Contact in Three-phase Reactors
Particle
Bubble
External Diffusion
Internal Diffusion
Catalytic Surface
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• Theory of Catalytic Gas- Liquid Reactions
• A(G) B(L) C
• Gaseous reactant A reacts with non-volatile
  liquid reactant B on solid catalyst sites.
• Mechanism Of Three- Phase Reactions-
• Mass Transfer of component A from bulk gas to
  gas-liquid
• interface
• Mass transfer of component A from gas-liquid
  interface to bulk
• liquid
• Mass transfer of A B from bulk liquid to
  catalyst surface
• Intraparticle diffusion of species A B through
  the catalyst pores
• to active sites.
• Adsorption of both or one of the reactant species
  on catalyst
• active sites
• Surface reaction involving at least one or both
  of the adsorbed
• species

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Common Flow Regimes in Industrial Catalytic
Gas- Liquid Reactors
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Design Models For Catalytic Gas- Liquid Reactors
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Correlations Used for the Three-Phase Catalytic
Reactors
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Correlations Used for the 2-Phase Reactors

• Gas Liquid Continuous Stirred Tank Reactor
• 1. Maximum Gas Flow rate (QGmax) Zwietering
  (1963)
• 2. Bubble diameter (db) Van Dierendonck (1970)
• 3. Gas holdup (?G) - Van Dierendonck (1970)
• 4. Liquid side Mass transfer coefficient (kL)
  Van Dierendonck (1970)
• 5. Liquid side Mass transfer coefficient (kL) for
  single bubbles - Hughmark(1971)
• Catalytic Liquid Fluidized Bed
• Mass Transfer Coefficient (KL) Chu, Kalil and
  Wetteroth (1953)
• Catalytic Gas Fluidized bed
• 1. Voidage at Minimum Fluidization (?mf)
  Broadhurst and Becker (1975)
• 2. Velocity at Minimum fluidization (Umf) Kunii
  and Levenspiel (1969 )
• 3. Bubble Diameter (DB)- Horio and Nonaka (1984)
• 4. Mass Transfer Coefficients (KBC and KCE)
  Kunni and Levenspiel (1969)
• 5. Coefficient for Axial Dispersion (DGA)
  Yoshida,Kunii and Levenspiel(1969)

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Calculation of Catalytic Effectiveness Factor

• Catalytic Effectiveness Factor
• where
• - Thiele Modulus
• 1st order reaction rate
• Spherical Pellet
• Cylindrical Pellet
• Slab Pellet

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Catalytic Fixed-Bed Reactor - Design Model

• Mass Balance around the catalyst
• Gas-Phase component mass balance (Plug Flow
  model)
• Gas-Phase component mass balance (Dispersion
  model)
• Energy Model

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Catalytic Gas-Fluidized Bed Reactor- Design Model

• Bulk Gas Phase( Bubble Phase)
• Plug Flow-
• With Axial Dispersion
• Intermediate(Cloud- Wake) Phase
• Catalyst (Emulsion) Phase
• Energy Balance

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Catalytic Liquid -Fluidized Bed Reactor-Design
Model

• Liquid-phase component balance
• Plug Flow-
• (1)
• Dispersion-
• 
  (2)
• Catalyst (Emulsion) Phase
• (3)
• Energy Balance-
• 
  (4)
  

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Gas-Liquid Agitated Tank- Design Model

• Gas-phase Component Mass Balance
• or
• 
  
  (1)
• Liquid-phase Volatile-Component Mass Balance
• 
  
  (2)
• Liquid-phase Non-Volatile-Component Mass Balance
• 
  
  (3)
• Energy Balance
• 
  
  

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Three-Phase Gas-Liquid Catalytic Reactor- Design
Model(Trickle-Bed, Fixed-upflow Bubble-Bed,
Bubble Slurry Bed, 3-Phase Fluidized Bed)

• Non-Volatile Liquid-phase mass balance
• Volatile Liquid-phase mass balance
• Boundary Conditions
• At Z0
• At ZL
• Gas-phase mass balance
• Component mass balance around the catalyst

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Three-Phase Gas-Liquid Catalytic Reactor- Design
Model (CSTR Slurry)

• Non-Volatile Component Liquid-phase mass balance
• 
  
  (1)
• Non-Volatile Component Liquid-phase mass balance
• 
  
  (2)
• Gas-phase mass balance
• (3)
  
• Component mass balance around the catalyst
• 
  (4)

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ReaCat Start up screen
Rate Law
Inlet Temperature and Pressure, Energy Model
Selection
Reaction Rate Constant
Physical Properties of Components
Reactor Specifications
Reaction Stoichiometry
Run
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REACTION
Reaction Phase Menu
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REACTOR TYPE

• Reactor Type Menu

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Global Options
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Physical Properties
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Reaction Stoichiometry
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Reaction Rate
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Rate Constant
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Reactor Specifications
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Graphical Output of the ReaCat Program
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Reactor Flow-Sheeting
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ReaCat, Test Cases
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ReaCat, Test Cases
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ReaCat, Test Cases
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ReaCat, Test Cases
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ReaCat, Test Cases
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Sulfuric Acid Production by Contact Process
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Parameters and Operating Conditions for the
Sulfuric Acid Contact Process
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Graph of Temperature v/s Tube Length for Contact
Process
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Graph of Concentration v/s Tube Length for
Contact Process
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Graph of Conversion v/s Tube Length for the
Contact Process
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SO2 Conversion v/s Inlet Temperature
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SO2 Conversion v/s Inlet
Flowrate
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CONCLUSION

• A Package for multi-phase catalytic and
  non-catalytic reactors has been developed which
  demonstrates the capability to handle complex
  Material and Energy Balances and associated
  correlations.
• Features to Be Added-
• Add a utility to perform reaction rate
  optimization. This is very useful when reaction
  rate is not known.
• Build a kinetic database of specific industries
  such as Sulfuric Acid and Ammonium Phosphate.