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SE 6: Liquid Liquid Extraction Equipment
SE 6: Liquid Liquid Extraction Equipment
Part 1: Introduction
1. SOLVENT EXTRACTION EQUIPMENT
1.1 Equipment Classification and Selection
1.2 Equipment Design
Part 2: The Classification and Selection of Solvent Extraction Contactors
1. INTRODUCTION
1.1 Background
1.2 Principles of Solvent Extraction Equipment
1.3 Current Usage of Extractor Equipment
1.4 Objectives and Layout
2.CONTACTOR CLASSIFICATION AND DEVELOPMENT
2.1 Contactor Classification Scheme
2.1.1 Classification Schemes Used in the Literature
2.1.2 Developed Scheme
2.2 Liquid-Liquid Extraction Contactors
2.2.1 Vertical Differential (Column) Contactors
2.2.2 Horizontal Differential Contactors
2.2.3 Vertical Staged Contactors
2.2.4 Horizontal Stagewise Contactors (Mixer-Settlers)
2.2.5 Centrifugal Extractors
2.2.6 Other Contactors
2.2.7 Equipment for Supercritical Extraction
3. EXTRACTORS IN COMMERCIAL USE
3.1 Random-Packed Column
3.2 Structured-Packed Column
3.3 Baffle-Plate Columns /Slat Tower
3.4 Sieve Plate (Sieve Tray) Column
3.5 Pulsed Packed Column
3.6 The Pulsed Perforated Plate Column
3.7 The Reciprocating Plate (Karr) Extraction Column
3.8 The Rotating Disc Contactor
3.9 The Asymmetric Rotating Disc Extractor
3.10 Oldshue-Rushton Column
3.11 The Scheibel Column
3.12 The Kuhni Column
3.13 The Raining Bucket (Graesser) Contactor
3.14 The Lurgi Extraction Tower
3.15 The Combined Mixer-Settler
3.16 The Integral Box Mixer-Settler
3.17 Pump Mix Mixer-Settlers
3.18 The IMI Mixer-Settler
3.19 Lurgi Mixer-Settlers
3.20 The Podbielniak Centrifugal Extractor
3.21 Alfa-Laval Centrifugal Extractor
3.22 The Westfalia Extractor
3.23 Eries Robatel BXP Centrifugal Extractor
3.24 The ANL/SRL Annular Centrifugal Extractor
3.25 The Luwesta Extractor
3.26 The Eries Robatel LX Centrifugal Extractor
3.27 Hydrocyclone and 'Fluidic' Extractors
3.28 Non-Dispersive Extraction: Hollow Fibre Membrane Extractors
4. CONTACTOR DESIGN AND SIZING
4.1 Introduction
4.2 Data Gathering
4.3 Design of Columns
4.3.1 Column Diameter
4.3.2 Column Height
4.3.3 Mechanical Design and Operation
4.3.4 Column Simulation
4.4 The Design of Mixer-Settlers
4.4.1 Settler Design
4.4.2 Mixer Design
4.4.3 Phase Dispersed
4.4.4 Secondary Haze
4.5 The Design of Centrifugal Contactors
4.5.1 Stagewise, Mixer-Settler, Contactors
4.5.2 Differential Contactors
5. CONTACTOR SELECTION
5.1 Selection Criteria Point Score Method
5.1.1 Data Needed
5.1.2 Selection Criteria
5.2 Decision Tree Method of Selection
5.2.1 Basic Selection Criteria
6. ANCILLARY EQUIPMENT
6.1 Agitation and Pulsing Equipment
6.2 Phase Disentrainment
6.3 Condition Monitoring and Control
6.3.1 Interface Detection and Control
6.3.2 Sampling Equipment
6.3.3 Future Developments
7. CONCLUSIONS
8. NOMENCLATURE
9.REFERENCES
10. APPENDIX A. CONTACTORS IN USE BY SPS SUBSCRIBING COMPANIES
11. APPENDIX B. EXAMPLES OF CONTACTOR SELECTION PROCEDURE
Part 3: Mathematical Methods
Part 4: Scale up of Liquid-Liquid Extraction Equipment
1 INTRODUCTION
1.1 Scale Up Philosophies
1.2 Contactor Characteristics
1.3 The Performance of Column Contactors
1.3.1 Throughput
1.3.2 Mass Transfer
1.3.3 Axial Mixing
1.4 The Performance of Mixer-Settlers
1.4.1 The Mixer
1.4.2 The Settler
1.5 General Aspects of Scale Up
2. UNAGITATED COLUMN CONTACTORS
2.1 Packed Columns
2.1.1 Hydrodynamics
2.1.2 Flooding
2.1.3 Drop Size
2.1.4 Hold-up
2.1.5 Mass Transfer
2.1.6 Axial Mixing
2.1.7 Less Fundamental Studies
2.1.8 Conclusions
2.2 Perforated Plate Columns
2.2.1 Introduction
2.2.2 Capacity
2.2.3 Mass Transfer Performance
2.2.4 Axial Mixing
2.2.5 Discussion
3. PULSED COLUMN CONTACTORS
3.1 Pulsed Perforated Plate Columns
3.1.1 Hydrodynamics
3.1.2 Drop Sizes
3.1.3 Mass Transfer Correlations
3.1.4 Axial Mixing
3.1.5 Constructional Details and Pulsation Methods
3.1.6 Conclusions
3.2 Reciprocating Plate Columns
3.2.1 Hydrodynamics
3.2.2 Mass Transfer Performance
3.2.3 Power Consumption
3.2.4 Prochazka Column
3.2.5 Conclusions
3.3 Pulsed Packed Columns
3.3.1 Hydrodynamics
3.3.2 Flooding
3.3.3 Drop Size
3.3.4 Mass Transfer
3.3.5 Pulsation Methods
3.3.6 Conclusions
4. ROTARY AGITATED CONTACTORS
4.1 Rotating Disc Contactors
4.1.1 Column Throughput
4.1.2 Drop Size
4.1.3 Axial Mixing and Mass Transfer
4.2 Asymmetric Rotating Disc Contactor
4.3 Oldshue-Rushton Column Contactor
4.4 Kuhni Column
4.4.1 Drop Size
4.4.2 Hold-up and Slip Velocity
4.4.3. Throughput
4.4.4 Axial Mixing
4.4.5 Scale Up
4.5 Scheibel Column
4.6 Raining Bucket Contactor
5. CENTRIFUGAL CONTACTORS
6. MIXER-SETTLERS
6.1 Power Input
6.2 Drop Size in the Mixer
6.3 Batch Kinetics
6.4 Rate Controlling Mechanisms and Scale up Relationships
6.5 Stability and Entrainment
6.6 Settler Area
6.7 Effect of Drop Size on Depth of Dispersion Band
6.8 Settler Shape
6.9 Entrainment from the Settler
7 CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE WORK
NOMENCLATURE
REFERENCES
Part 5: Column Design
1. INTRODUCTION
1.1 Basic Phenomena in Liquid-Liquid Extraction Column Contactors
1.1.1 Industrial column contactors
1.1.2 Agitation mechanisms
1.1.3 Hydrodynamic factors; throughput and flooding
1.1.4 Factors affecting mass transfer
1.1.5 Selection of dispersed phase
1.1.6 Axial mixing; definitions, effects and measurement
1.2 Constraints on Contactor Selection
1.2.1 Volumetric throughput and number of transfer units
1.2.2 System physical properties
1.2.3 Other constraints
1.3 Arrangement of Design Report
2. DESIGN SUMMARY
2.1 Design Flow Diagram
2.2 Basic Design Equations
3. BASIC DATA
3.1 Physical Properties
3.1.1 Density
3.1.2 Viscosity
3.1.3 Interfacial tension
3.2 Molecular Diffusivity
3.3 Equilibrium Data
3.4 Liquid-Liquid-Solid Wetting Properties
4. PRELIMINARY CALCULATIONS
4.1 Number of Transfer Units and Flow Ratio
4.1.1 Single transferring solute
4.1.2 Multiple Interacting solutes
4.2 Specific Throughput and Limits on Diameter
4.3 Phase Dispersed
4.4 Preliminary Contactor Selection
4.5 Estimate of Internal Geometry
4.5.1 Critical packing size
4.5.2 Packing type and material
4.5.3 Critical sieve plate perforation or nozzle diameter
4.5.4 Compartment height
4.5.5 Plate free area, and perforation and aperture diameters
4.5.6 Rotor diameter
4.6 Intensity of Agitation and Power Consumption
4.6.1 Pulse amplitude and frequency in a pulsed column
4.6.2 Rotor speed in a rotary-agitated column
4.6.3 Total and specific power input
4.7 Future Developments
5 HYDRODYNAMICS, OPERATING VELOCITIES AND COLUMN DIAMETER
5.1 Calculation of Flooding Velocity
5.1.1 Drop size prediction
5.1.2 Terminal velocities
5.1.3 Characteristic velocities
5.1.4 Calculation of exponent in Richardson and Zaki equation for slip velocity
5.1.5 Calculation of velocity and hold-up at flooding due to drop rejection from column
5.2 Flooding Conditions due to Insufficient Pulsation in a Pulsed Sieve Plate Column
5.3 Operating Velocities and Hold-up
5.4 Revised Column Diameter
5.5 Future Developments
6. MASS TRANSFER
6.1 Mass Transfer Coefficients
6.1.1 Continuous phase mass transfer coefficient
6.1.2 Dispersed phase mass transfer coefficient
6.1.3 Overall mass transfer coefficients
6.2 Height of Transfer Unit in Plug Flow
7. AXIAL MIXING AND CORRECTED COLUMN HEIGHT
7.1 Axial Mixing Coefficients
7.1.1 Packed columns
7.1.2 Pulsed sieve plate columns
7.1.3 RDC/ARDC
7.1.4 Kuhni column
7.2 Calculation of Column Height Corrected for Axial Mixing
7.2.1 Single or non-interacting solutes and linear equilibrium: method of Pratt
7.2.2 Multiple interacting solutes: method of Ricker et al (1981)
8. MECHANICAL DESIGN AND OPERATION
8.1 End Section and Phase Distribution Design
8.1.1 Design of dispersed phase distributor
8.1.2 Disengaging zone
8.2 Interface Detection and Control
8.2.1 Interface detection for automatic control
8.2.2 External settler
8.3 Agitation Equipment
8.3.1 Pulsed columns
8.3.2 Rotary-agitated columns
8.4 Start-up and Shut-down
8.5 Sampling
8.6 Suspended and Interfacial Contamination
9. SCALE-UP OF PROVEN COLUMN DESIGN
9.1 General Principles
9.1.1 Effect of scale on HTU for specific equipment
10. FINAL CONTACTOR SELECTION
10.1 Materials of Construction
10.1.1 Structural materials
10.1.2 Sealing materials
10.1.3 Laboratory compatibility tests for materials
11. SAFETY AND ENVIRONMENTAL CONSIDERATIONS
12. ACKNOWLEDGEMENTS
13 NOMENCLATURE
14 REFERENCES
15 APPENDIX 1 PHYSICAL PROPERTIES OF LIQUID-LIQUID SYSTEMS
16 APPENDIX 2 WORKED EXAMPLE
16.1 Problem Setting
16.1.1 Physical Properties
16.1.2 Equilibrium Data
16.2 Design Calculations: Packed Column
16.2.1 First Iteration
16.2.2 Packed Column: Second Iteration
16.2.3 Packed Column: Third Iteration
16.3 Design Calculation: RDC
16.3.1 First Iteration
16.3.2 RDC Design: Second Iteration
16.4 Design Calculation: Pulsed Column
16.4.1 MEK Balance
16.4.2 Number of Transfer Units
16.4.3 Calculation of Parameters Specific to a Pulsed Column
16.4.4 Drop Size Calculation
16.4.5 Terminal Velocities
16.4.6 Characteristic Velocity Uo
16.4.7 Calculation of Flooding Velocity
16.4.8 Operating Velocity
16.4.9 Holdup under Operating Conditions
16.4.10 Revised Column Diameter
16.4.11 Mass Transfer Calculations
16.4.12 Height of Plug Flow Transfer Unit
16.4.13 Column Height for Plug Flow
16.5 Preliminary Contactor Selection
16.6 Calculation of Column Height Corrected for Axial Mixing in RDC
16.6.1 Calculation of Continuous Phase Peclet Number
16.6.2 Extraction Parameters (Equations 7.8 and 7.10)
16.6.3 Coefficients b 1 , l 1 , a 4 (Equations 7.12c, 7.13c, 7.17c, 7.18)
16.6.4 Corrected Column Height Z (Equation 7.19c)
Part 6: Integral Box Mixer Settlers
1. INTRODUCTION
1.1 Objectives of a mixer-settler
1.2 Factors governing performance of mixer
1.3 Factors governing performance of settler
1.4 Principal existing types of mixer-settler
1.5 The integral box mixer-settler
2. THE DESIGN APPROACH
2.1 Discussion
2.2 Summary of design approach
2.3 Basic Design Guide
3. GENERATION OF PRELIMINARY DATA
3.1 Physical properties
3.2 Separating funnel work and standardised mixing tanks
3.3 Equilibrium data
3.4 Kinetic data
3.5 Phase separation characteristics from batch tests
3.6 Choice of phase to disperse and hold-up considerations
3.7 Choice of temperature of operation
4. PRELIMINARY MIXER-SETTLER DESIGN
4.1 Volume of mixing vessel
4.2 Pressure drop through ports between mixer and settler
4.3 Flow rate over weirs
4.4 Calculation of liquid levels in the settler
4.5 Minimum solvent depth
4.6 Summary of procedure for non-submerged top weirs
4.7 Total liquid heights for submerged top weirs
4.8 Summary of procedure for submerged top weirs
4.9 Effect of dispersion band thickness
4.10 Effect of density variations
4.11 Effect of interface level above mixed phase port
4.12 Settler area
5. PILOT PLANT
5.1 Design from batch data
5.2 Objectives of experimental programme
6. FINAL MIXER-SETTLER DESIGN
6.1 Finalise decision on operation with non-submerged or submerged top weir
6.2 Finalise shape of mixer
6.3 Finalise settler area for gravity separation without baffles
6.4 Settler improvement with baffles and packings
6.5 Position of impeller
6.6 Choice of impeller speed, impeller diameter and power requirement (1)
6.7 Scale-up procedures
6.8 Entrainment
6.9 Design of terminal stages
6.10 Design uncertainties
7. OPERATIONAL CONSIDERATIONS
7.1 Start-up and Shut Down
7.2 Dynamic characteristics and control
7.3 Sampling and control measurements
7.4 Flooding and inversion
7.5 Crud formation and treatment
7.6 Evaporative losses
7.7 Recovery of entrained phases
7.8 Materials of construction
7.9 Safety and environmental considerations
7.10 Improving the performance of existing mixer-settlers
7.11 Application of integral box design method to pump-mixer-settler
8. REFERENCES
9. NOMENCLATURE
10. APPENDIX 1
11. APPENDIX 2 Examples of design calculations
11.1 Design basis
11.2 Estimation of mixer volume and stage efficiency from batch tests
11.3 First estimate of dispersion band thickness/flow equation from batch test
11.4 Volume of mixing vessel
11.5 Pressure drops through ports
11.6 Flow rate over weirs
11.7 Example calculation of levels for non-submerged top weirs
11.8 Example calculation of levels with submerged top weirs
11.9 Example calculation of interface level effect
11.10 Calculation of settler dimensions
11.11 Scale-up of batch data using power/unit volume
11.12 Scale-up of batch data using constant tip speed
Part 7: Pump-mix Mixer Settlers
1. INTRODUCTION
1.1 The pump-mix impeller
1.2 Aspects of pump-mix impeller performance
1.3 Settler designs
1.4 Aspects of settler performance
1.5 The pump-mix mixer-settler
2. THE DESIGN APPROACH
2.1 Introduction
2.2 Basic design guide
2.2.1 Physical properties
2.2.2 Estimation of stage efficiencies (Appendix 3)
2.2.3 Mixer size
2.2.4 Estimated impeller size, speed and power ranges (Section 6.2)
2.2.5 Design a pilot plant mixer (Appendix 5.1 to 5.4 and 5.6)
2.2.6 Pumping requirements (Section 4.5) (Appendix 5.5)
2.2.7 Extraction rate (Appendix 6.2)
2.2.8 Full scale design
2.2.9 Settler design
3. GENERATION OF PRELIMINARY DATA AND INTERPRETATION
3.1 Physical properties
3.2 Separating funnel work and standardized mixing tanks
3.3 Equilibrium data
3.4 Kinetic data
3.5 Phase separation rate tests
3.6 Choice of phase to disperse and hold-up considerations
3.7 Choice of temperature of operation
4. PRELIMINARY MIXER DESIGN
4.1 Mixer design principles
4.2 Equilibrium considerations
4.3 Mixer configuration
4.4 Kinetic considerations
4.5 Pumping performance
4.6 Other aspects of mixer performance
4.7 Recommendations for preliminary mixer design
5. PRELIMINARY SETTLER DESIGN
5.1 Settler design principles
5.2 Settler configuration
5.3 Inlet arrangements
5.4 Flow patterns in settlers
5.5 Weir and off-take points
5.6 Settler liquid depths
5.7 Multi-tray settlers
5.8 Coalescers
5.9 Entrainment
5.10 Removal of haze
5.11 Baffles and deep dispersion bands
5.12 General comments
6. PILOT PLANT
6.1 Design from batch data
6.2 Impeller characterization
6.3 Objectives of experimental programme
7. FINAL MIXER-SETTLER DESIGN
7.1 Impeller type and pumping methods
7.2 Configuration of mixer
7.3 Positions of impellers and inlets
7.4 Impeller size, speed, power
7.5 Configuration of settler
7.6 Settler inlet arrangement
7.7 Settler internals
7.8 Weirs
7.9 Design uncertainties
8. OPERATIONAL CONSIDERATIONS
8.1 Start-up and shut-down
8.2 Dynamic characteristics and control
8.3 Interface level and sampling
8.4 Flooding and inversion
8.5 Crud formation and treatment (Ritcey and Ashbrook, 1979)
8.6 Evaporative losses
8.7 Materials of construction (Ritcey and Ashbrook, 1979)
8.8 Safety and environmental considerations
8.9 Improving the performance of existing mixer-settlers
9. REFERENCES
10. NOMENCLATURE
11. APPENDIX 1 Approximate Properties at 20 to 30 'C
12. APPENDIX 2 EXAMPLE CALCULATIONS
13. APPENDIX 3 Estimates for Continuous Extraction from Batch Data
14. APPENDIX 4 Preliminary Design of Full Scale Plant from Batch Data
14.1 A4.1 Residence time
14.2 A4.2 Mixer volume
14.3 A4.3 Impeller speed
15. APPENDIX 5 Pilot Plant Design
15.1 A5.1 Residence time
15.2 A5.2 Mixer volume
15.3 A5.3 Impeller speed
15.4 A5.4 Impeller selection
15.5 A5.5 Pumping considerations
15.6 A5.6 Power consumption
15.7 A5.7 Operational considerations
16. APPENDIX 6 Collection of Pilot Plant Data
16.1 A6.1 Pumping characteristics
16.2 A6.2 Extraction rate
17. APPENDIX 7 Full Scale Mixer Design
17.1 A7.1 Extraction rate
17.2 A7.2 Pumping capacity
17.3 A7.3 Pumping head requirement
18. APPENDIX 8 Solvent Depth in an Integral Box Mixer-Settler
19. APPENDIX 9 Analysis of Separation Rate Data
20. APPENDIX 10 Design of Settler Using Separation Rate Data
21. APPENDIX 11 Multi-Tray Coalescer
22. APPENDIX 12 Baffles and Deep Dispersion Bands
Part 8: Gravity Settlers
1. INTRODUCTION
1.1 Aim and Scope of Design Report
1.2 Design Constraints
1.2.1 Process constraints
1.2.2 Mixer constraints
1.3 Classes of Industrial Settler
1.3.1 Bulk flow mainly horizontal
1.3.2 Bulk flow mainly radial/vertical
1.3.3 Bulk flow vertical: split dispersion band
1.3.4 Multi-tray settlers
1.3.5 Centrifugal settler
1.4 Special Case: Clarification by Sedimentation; Coalescence not Rate-limiting
1.5 Models for Liquid-Liquid Disengagement: The State of the Art
1.5.1 Overall features of dispersion disengagement in a settler
1.5.2 Mechanisms of coalescence
1.5.3 The relationship between dispersion band height and disengagement velocity in continuous flow and batch experiments
1.6 Superficial and Slip velocities in Differential and Continuous Disengagement
1.6.1 Differential
1.6.2 Continuous flow
2. DESIGN GUIDE
2.1 The Design Flowcharts
2.2 Summary
2.3 Basic Design Equations
3. PREDICTION OF CONTINUOUS FLOW DISPERSION BAND HEIGHT AS A FUNCTION OF DISENGAGEMENT VELOCITY
3.1 Basis of the Calculations
3.2 Procedure for a Stopped-Flow Differential Disengagement Test
3.2.1 Laboratory mixer
3.2.2 Procedure
3.3 Interpretation of Disengagement Results
3.3.1 Types of differential disengagement curve
3.3.2 Sedimentation with interdrop coalescence
3.3.3 Simple exponential decay of dispersion height
4. DIMENSIONS OF THE DISENGAGING ZONE
4.1 Choice of Dispersion Band Depth or Flow Velocity
4.2 Alternative Settler Shapes
4.3 Dimensions for a Rectangular Settler
4.4 Dimensions for a Diverging Settler
5. INTERNALS OF THE GRAVITY SETTLER
5.1 Inlet Arrangement
5.1.1 Aim of good inlet design
5.1.2 Design of the mixed phase inlet port
5.2 Role of Turbulence-Calming and Flow Redistribution Devices
5.2.1 Number of baffle elements
5.3 Outlet Arrangement
5.3.1 Horizontal velocity of separated phases
5.4 Dimensions of Weirs and Ports
5.4.1 Height of light phase weir
5.4.2 Height of heavy phase weir
5.4.3 Height of dispersed phase in preceding mixer
5.4.4 Thickness of slot ports
5.5 The Function of a Dam Baffle Within the Settler
5.6 Other Internals
6. DESIGN STRATEGEM FOR OTHER GEOMETRIES
6.1 Combined Mixer-Settler
6.1.1 Mode of operation
6.1.2 Dispersion band heights in the CMS
6.1.3 Height of heavy phase weir
6.2 Multi-Tray Settler
6.2.1 Criteria for selection of multi-tray design
6.2.2 Proprietary designs
6.2.3 Sizing an IMI multi-tray settler
6.2.4 Upgrading of an existing box settler
6.2.5 Sizing a Lurgi multi-tray settler
6.2.6 Multi-tray devices for secondary dispersions
6.3 Centrifugal Separators
6.4 The Disengaging Zone of a Column Contactor
6.4.1 Sizing of disengaging zone from a batch test
7. OPERATIONAL CONSIDERATIONS
7.1 Start-up and Shut-down
7.2 Dynamic Flowrate Variations and Control
7.3 Instrumentation
7.4 Crud Control
7.5 Safety of Settlers and Associated Plant
8. MATERIALS OF CONSTRUCTION
8.1 Structural materials
8.2 Sealing Materials
8.3 Laboratory Compatibility Tests for Settler Materials
9. REFERENCES
10. NOMENCLATURE
11. APPENDIX 1 WORKED EXAMPLES
11.1 EXAMPLE 1 (S-SHAPED COALESCENCE CURVE)
11.2 EXAMPLE 2 ('EXPONENTIAL' DECAYING COALESCENCE CURVE)
12. APPENDIX 2 DERIVATION OF EQUATIONS FOR DIFFERENTIAL AND CONTINUOUS FLOW DISENGAGEMENT
12.1 A2.1 Drop growth during sedimentation
12.2 A2.2 Sedimentation velocities
12.3 A2.3 Derivation of sedimenting zone parameters from a differential sedimentation curve
12.4 A2.4 Sedimentation in continuous flow, height of the dispersion band
12.5 A2.5 Simplified, high Reynolds Number, analysis
Part 9: Design of Tank Reactors for the Processing of Dispersed Liquid Systems
1. INTRODUCTION TO THE DESIGN OF TANK REACTORS
1.1 General Design Features of Tank Reactors
1.2 Physical, Kinetic and Transport Data Collation
1.3 Equations of Conservation of Mass and Energy in a Tank Reactor
1.4 Arrangement of This Part
2. DESIGN SUMMARY
3. CHEMICAL REACTION KINETICS
3.1 Batch Reactors
3.1.1 Mass Transfer Controlled Process
3.1.2 Chemical Reaction Controlled Process
3.1.3 Batch: Reactions in both Phases
3.2 Two Phase Continuous Flow Reactors
3.2.1 Cross Flow Operation
3.2.2 Counterflow Operation
3.3 Short Cut Design Procedure
3.4 Choice of Reactor System
3.4.1 Yield and Selectivity
3.4.2 Safety
4. AGITATION DESIGN AND RESIDENCE TIME DISTRIBUTION
4.1 Agitator Design and Selection
4.1.1 Basic Flow Patterns and Bulk Velocities in Agitated Tanks
4.1.2 Agitator Types
4.1.3 Emulsion Formation
4.1.4 Vortex Formation and Suppression
4.1.5 Agitator Selection
4.1.6 Uniformity of Dispersion
4.1.7 Power Requirements for Agitation
4.1.8 Time For Uniform Blending
4.2 Residence Time Distributions
4.2.1 The F Diagram and Response to a Step Change
4.2.2 Interpretation of Age Distribution Diagrams
4.2.3 Residence Time Distributions in Two Phase Systems
4.2.4 Complex Reactions
5. HOLD-UP, DROP SIZE AND INTERFACIAL AREA
5.1 Dispersed Phase Hold-Up
5.2 Minimum Impeller Speed
5.2.1 Complete Mixing
5.2.2 Uniform Dispersion
5.3 Choice of Phase Dispersed
5.3.1 Batch Operation
5.3.2 Continuous Operation
5.3.3 Phase Inversion
5.4 Interfacial Area
5.5 Drop Size Prediction
5.5.1 Continuous Flow Systems
5.5.2 Unbaffled Vessels
5.5.3 The Effect of Surfactants or Stabilisers
5.6 Drop Size Distributions
6. HEAT TRANSFER
6.1 Heat Transfer Considerations
6.2 Agitated-Liquid Side Heat Transfer
6.3 Coil or Jacket-Side Coefficients
7. SCALE-UP CONSIDERATIONS
7.1 Scale-Up: Empirical Rules
7.1.1 Scale-Up for Equivalent Dispersion
7.1.2 Scale-Up on Equal Peripheral Speed
7.1.3 Scale-Up for Heat Transfer
7.1.4 Scale-Up of Continuous Dispersion Operations
7.1.5 Scale-Up for Constant Mixing Time
8. APPENDIX 1: WORKED EXAMPLES
8.1 Design of a Suspension Polymerisation Reactor (Overall Design)
8.1.1 Reaction Kinetics of the Polymerisation of Styrene
8.1.2 Reactor Selection - Batch vs Continuous
8.1.3 Design of CSTR
8.1.4 Energy Requirements
8.1.5 Impeller Speed (N)
8.1.6 Dispersed Phase Hold-up and Interfacial Area
8.1.7 Materials of Construction
8.1.8 Control
8.1.9 Safety Considerations
8.1.10 Pressure Relief
8.2 Calculation of the Ideal Number of Mixer-Settler Stages (Section 3.2)
8.3 Short Cut Reactor Design Procedure (Section 3.3)
8.4 Reactor Size Calculation Allowing for Drop Interaction (Section 4.1.6)
8.5 Estimation of Power Consumption for a Turbine (Section 4.1.7)
8.6 Calculation of Time for Complete Neutralisation (Section 4.1.8)
8.7 E and F Table Analysis for Residence Times (Section 4.2.1)
8.8 Determination of Mean Residence Time Using F Diagrams (Section 4.2.1)
8.9 Calculation of Sauter Mean Drop Size (Section 5.3)
8.10 Estimation of Hold-up (Section 5.5)
8.11 Minimum Agitator Speed for Uniform Dispersion (Section 5.6)
