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Design of Multiphase Reactors

Design of Multiphase Reactors

Vishwas G. Pangarkar

ISBN: 978-1-118-80776-7

Dec 2014

536 pages

$100.99

Description

Details simple design methods for multiphase reactors in the chemical process industries

  • Includes basic aspects of transport in multiphase reactors and the importance of relatively reliable and simple procedures for predicting mass transfer parameters
  • Details of design and scale up aspects of several important types of multiphase reactors
  • Examples illustrated through design methodologies presenting different reactors for reactions that are industrially important
  • Includes simple spreadsheet packages rather than complex algorithms / programs or computational aid

Foreword xv

Preface xvii

1 Evolution of the Chemical Industry and Importance of Multiphase Reactors 1

1.1 Evolution of Chemical Process Industries 1

1.2 Sustainable and Green Processing Requirements in the Modern Chemical Industry 4

1.3 Catalysis 9

1.3.1 Heterogeneous Catalysis 11

1.3.2 Homogeneous Catalysis 16

1.4 Parameters Concerning Catalyst Effectiveness in Industrial Operations 17

1.4.1 Chemoselectivity 19

1.4.2 Regioselectivity 19

1.4.3 Stereoselectivity 19

1.5 Importance of Advanced Instrumental Techniques in Understanding Catalytic Phenomena 20

1.6 Role of Nanotechnology in Catalysis 21

1.7 Click Chemistry 21

1.8 Role of Multiphase Reactors 22

References 23

2 Multiphase Reactors: The Design and Scale-Up Problem 30

2.1 Introduction 30

2.2 The Scale-Up Conundrum 31

2.3 Intrinsic Kinetics: Invariance with Respect to Type/Size of Multiphase Reactor 34

2.4 Transport Processes: Dependence on Type/Size of Multiphase Reactor 34

2.5 Prediction of the Rate-Controlling Step in the Industrial Reactor 35

2.6 Laboratory Methods for Discerning Intrinsic Kinetics of Multiphase Reactions 35

2.6.1 Two-Phase (Gas–Liquid) Reaction 35

2.6.2 Three-Phase (Gas–Liquid–Solid) Reactions with Solid Phase Acting as Catalyst 41

Nomenclature 44

References 45

3 Multiphase Reactors: Types and Criteria for Selection for a Given Application 47

3.1 Introduction to Simplified Design Philosophy 47

3.2 Classification of Multiphase Reactors 48

3.3 Criteria for Reactor Selection 48

3.3.1 Kinetics vis-à-vis Mass Transfer Rates 49

3.3.2 Flow Patterns of the Various Phases 50

3.3.3 Ability to Remove/Add Heat 50

3.3.4 Ability to Handle Solids 53

3.3.5 Operating Conditions (Pressure/Temperature) 54

3.3.6 Material of Construction 54

3.4 Some Examples of Large-Scale Applications of Multiphase Reactors 55

3.4.1 Fischer–Tropsch Synthesis 55

3.4.2 Oxidation of p-Xylene to Purified Terephthalic Acid for Poly(Ethylene Terephthalate) 67

Nomenclature 80

References 81

4 Turbulence: Fundamentals and Relevance to Multiphase Reactors 87

4.1 Introduction 87

4.2 Fluid Turbulence 88

4.2.1 Homogeneous Turbulence 89

4.2.2 Isotropic Turbulence 90

4.2.3 Eddy Size Distribution and Effect of Eddy Size on Transport Rates 90

Nomenclature 91

References 91

5 Principles of Similarity and Their Application for Scale-Up of Multiphase Reactors 93

5.1 Introduction to Principles of Similarity and a Historic Perspective 93

5.2 States of Similarity of Relevance to Chemical Process Equipments 94

5.2.1 Geometric Similarity 95

5.2.2 Mechanical Similarity 96

5.2.3 Thermal Similarity 100

5.2.4 Chemical Similarity 100

5.2.5 Physiological Similarity 101

5.2.6 Similarity in Electrochemical Systems 101

5.2.7 Similarity in Photocatalytic Reactors 102

Nomenclature 102

References 104

6 Mass Transfer in Multiphase Reactors: Some Theoretical Considerations 106

6.1 Introduction 106

6.2 Purely Empirical Correlations Using Operating Parameters and Physical Properties 107

6.3 Correlations Based on Mechanical Similarity 108

6.3.1 Correlations Based on Dynamic Similarity 108

6.4 Correlations Based on Hydrodynamic/Turbulence Regime Similarity 116

6.4.1 The Slip Velocity Approach 116

6.4.2 Approach Based on Analogy between Momentum and Mass Transfer 132

Nomenclature 135

References 138

7A Stirred Tank Reactors for Chemical Reactions 143

7A.1 Introduction 143

7A.1.1 The Standard Stirred Tank 143

7A.2 Power Requirements of Different Impellers 147

7A.3 Hydrodynamic Regimes in Two-Phase (Gas–Liquid) Stirred Tank Reactors 148

7A.3.1 Constant Speed of Agitation 150

7A.3.2 Constant Gas Flow Rate 150

7A.4 Hydrodynamic Regimes in Three-Phase (Gas–Liquid–Solid) Stirred Tank Reactors 153

7A.5 Gas Holdup in Stirred Tank Reactors 155

7A.5.1 Some Basic Considerations 155

7A.5.2 Correlations for Gas Holdup 164

7A.5.3 Relative Gas Dispersion (N/NCD) as a Correlating Parameter for Gas Holdup 165

7A.5.4 Correlations for NCD 166

7A.6 Gas–Liquid Mass Transfer Coefficient in Stirred Tank Reactor 166

7A.7 Solid–Liquid Mass Transfer Coefficient in Stirred Tank Reactor 175

7A.7.1 Solid Suspension in Stirred Tank Reactor 175

7A.7.2 Correlations for Solid–Liquid Mass Transfer Coefficient 191

7A.8 Design of Stirred Tank Reactors with Internal Cooling Coils 194

7A.8.1 Gas Holdup 194

7A.8.2 Critical Speed for Complete Dispersion of Gas 194

7A.8.3 Critical Speed for Solid Suspension 195

7A.8.4 Gas–Liquid Mass Transfer Coefficient 195

7A.8.5 Solid–Liquid Mass Transfer Coefficient 196

7A.9 Stirred Tank Reactor with Internal Draft Tube 196

7A.10 Worked Example: Design of Stirred Reactor for Hydrogenation of Aniline to Cyclohexylamine (Capacity: 25000 Metric Tonnes per Year) 198

7A.10.1 Elucidation of the Output 201

Nomenclature 203

References 206

7B Stirred Tank Reactors for Cell Culture Technology 216

7B.1 Introduction 216

7B.2 The Biopharmaceutical Process and Cell Culture Engineering 224

7B.2.1 Animal Cell Culture vis-à-vis Microbial Culture 224

7B.2.2 Major Improvements Related to Processing of Animal Cell Culture 225

7B.2.3 Reactors for Large-Scale Animal Cell Culture 226

7B.3 Types of Bioreactors 229

7B.3.1 Major Components of Stirred Bioreactor 230

7B.4 Modes of Operation of Bioreactors 230

7B.4.1 Batch Mode 231

7B.4.2 Fed-Batch or Semibatch Mode 232

7B.4.3 Continuous Mode (Perfusion) 233

7B.5 Cell Retention Techniques for Use in Continuous Operation in Suspended Cell Perfusion Processes 233

7B.5.1 Cell Retention Based on Size: Different Types of Filtration Techniques 234

7B.5.2 Separation Based on Body Force Difference 242

7B.5.3 Acoustic Devices 246

7B.6 Types of Cells and Modes of Growth 253

7B.7 Growth Phases of Cells 254

7B.8 The Cell and Its Viability in Bioreactors 256

7B.8.1 Shear Sensitivity 256

7B.9 Hydrodynamics 264

7B.9.1 Mixing in Bioreactors 264

7B.10 Gas Dispersion 273

7B.10.1 Importance of Gas Dispersion 273

7B.10.2 Effect of Dissolved Carbon Dioxide on Bioprocess Rate 275

7B.10.3 Factors That Affect Gas Dispersion 277

7B.10.4 Estimation of NCD 278

7B.11 Solid Suspension 279

7B.11.1 Two-Phase (Solid–Liquid) Systems 279

7B.11.2 Three-Phase (Gas–Liquid–Solid) Systems 280

7B.12 Mass Transfer 281

7B.12.1 Fractional Gas Holdup (εG) 281

7B.12.2 Gas–Liquid Mass Transfer 281

7B.12.3 Liquid–Cell Mass Transfer 283

7B.13 Foaming in Cell Culture Systems: Effects on Hydrodynamics and Mass Transfer 285

7B.14 Heat Transfer in Stirred Bioreactors 287

7B.15 Worked Cell Culture Reactor Design Example 291

7B.15.1 Conventional Batch Stirred Reactor with Air Sparging for Microcarrier-Supported Cells: A Simple Design Methodology for Discerning the Rate-Controlling Step 291

7B.15.2 Reactor Using Membrane-Based Oxygen Transfer 294

7B.15.3 Heat Transfer Area Required 294

7B.16 Special Aspects of Stirred Bioreactor Design 295

7B.16.1 The Reactor Vessel 296

7B.16.2 Sterilizing System 296

7B.16.3 Measurement Probes 296

7B.16.4 Agitator Seals 297

7B.16.5 Gasket and O-Ring Materials 297

7B.16.6 Vent Gas System 297

7B.16.7 Cell Retention Systems in Perfusion Culture 297

7B.17 Concluding Remarks 298

Nomenclature 298

References 301

8 Venturi Loop Reactor 317

8.1 Introduction 317

8.2 Application Areas for the Venturi Loop Reactor 317

8.2.1 Two Phase (Gas–Liquid Reactions) 318

8.2.2 Three-Phase (Gas–Liquid–Solid-Catalyzed) Reactions 319

8.3 Advantages of the Venturi Loop Reactor: A Detailed Comparison 323

8.3.1 Relatively Very High Mass Transfer Rates 323

8.3.2 Lower Reaction Pressure 324

8.3.3 Well-Mixed Liquid Phase 325

8.3.4 Efficient Temperature Control 325

8.3.5 Efficient Solid Suspension and Well-Mixed Solid (Catalyst) Phase 325

8.3.6 Suitability for Dead-End System 326

8.3.7 Excellent Draining/Cleaning Features 326

8.3.8 Easy Scale-Up 326

8.4 The Ejector-Based Liquid Jet Venturi Loop Reactor 326

8.4.1 Operational Features 328

8.4.2 Components and Their Functions 328

8.5 The Ejector–Diffuser System and Its Components 332

8.6 Hydrodynamics of Liquid Jet Ejector 333

8.6.1 Flow Regimes 336

8.6.2 Prediction of Rate of Gas Induction 341

8.7 Design of Venturi Loop Reactor 358

8.7.1 Mass Ratio of Secondary to Primary Fluid 358

8.7.2 Gas Holdup 367

8.7.3 Gas–Liquid Mass Transfer: Mass Transfer Coefficient (kLa) and Effective Interfacial Area (a) 376

8.8 Solid Suspension in Venturi Loop Reactor 385

8.9 Solid–Liquid Mass Transfer 388

8.10 Holding Vessel Size 389

8.11 Recommended Overall Configuration 389

8.12 Scale-Up of Venturi Loop Reactor 390

8.13 Worked Examples for Design of Venturi Loop Reactor: Hydrogenation of Aniline to Cyclohexylamine 390

Nomenclature 395

References 399

9 Gas-Inducing Reactors 407

9.1 Introduction and Application Areas of Gas-Inducing Reactors 407

9.1.1 Advantages 408

9.1.2 Drawbacks 408

9.2 Mechanism of Gas Induction 409

9.3 Classification of Gas-Inducing Impellers 410

9.3.1 1–1 Type Impellers 410

9.3.2 1–2 and 2–2 Type Impellers 416

9.4 Multiple-Impeller Systems Using 2–2 Type Impeller for Gas Induction 429

9.4.1 Critical Speed for Gas Induction 431

9.4.2 Rate of Gas Induction (QG) 431

9.4.3 Critical Speed for Gas Dispersion 434

9.4.4 Critical Speed for Solid Suspension 436

9.4.5 Operation of Gas-Inducing Reactor with Gas Sparging 439

9.4.6 Solid–Liquid Mass Transfer Coefficient (KSL) 440

9.5 Worked Example: Design of Gas-Inducing System with Multiple Impellers for Hydrogenation of Aniline to Cyclohexylamine (Capacity:

25000 Metric Tonnes per Year) 441

9.5.1 Geometrical Features of the Reactor/Impeller (Dimensions and Geometric Configuration as per Section 7A.10 and Figure 9.9

Respectively) 441

9.5.2 Basic Parameters 442

Nomenclature 443

References 446

10 Two- and Three-Phase Sparged Reactors 451

10.1 Introduction 451

10.2 Hydrodynamic Regimes in TPSR 452

10.2.1 Slug Flow Regime 452

10.2.2 Homogeneous Bubble Flow Regime 452

10.2.3 Heterogeneous Churn-Turbulent Regime 454

10.2.4 Transition from Homogeneous to Heterogeneous Regimes 455

10.3 Gas Holdup 457

10.3.1 Effect of Sparger 458

10.3.2 Effect of Liquid Properties 458

10.3.3 Effect of Operating Pressure 460

10.3.4 Effect of Presence of Solids 461

10.4 Solid–Liquid Mass Transfer Coefficient (KSL) 466

10.4.1 Effect of Gas Velocity on KSL 466

10.4.2 Effect of Particle Diameter dP on KSL 467

10.4.3 Effect of Column Diameter on KSL 467

10.4.4 Correlation for KSL 468

10.5 Gas–Liquid Mass Transfer Coefficient (kLa) 468

10.6 Axial Dispersion 472

10.7 Comments on Scale-Up of TPSR/Bubble Columns 474

10.8 Reactor Design Example for Fischer–Tropsch Synthesis Reactor 474

10.8.1 Introduction 474

10.8.2 Physicochemical Properties 475

10.8.3 Basis for Reactor Design Material Balance and Reactor Dimensions 476

10.8.4 Calculation of Mass Transfer Parameters 476

10.8.5 Estimation of Rates of Individual Steps and Determination of the Rate Controlling Step 478

10.8.6 Sparger Design 480

10.9 TPSR (Loop) with Internal Draft Tube (BCDT) 481

10.9.1 Introduction 481

10.9.2 Hydrodynamic Regimes in TPSRs with Internal Draft Tube 481

10.9.3 Gas–Liquid Mass Transfer 482

10.9.4 Solid Suspension 488

10.9.5 Solid–Liquid Mass Transfer Coefficient (KSL) 490

10.9.6 Correlation for KSL 490

10.9.7 Application of BCDT to Fischer–Tropsch Synthesis 491

10.9.8 Application of BCDT to Oxidation of p-Xylene to Terephthalic Acid 492

Nomenclature 493

References 496

Index 505

 "The book presents the current state-of-the-art technology and can serve as a good starting point for graduates planning to work on gas-liquid or gas-liquid-solid reactors. " (The Chemical Engineer, April 2016)

"The book would help academics to develop course material for process safety studies." (The Chemical Engineer, April 2016)


"Pangarkar is highly recommended: it may even help to minimize the number of blunders on a small scale." (N. Kuipers, April 2016)

"This book presents excellent discussion of the latest literature on the subject and brings out the gaps that need to be bridged. Simple concepts have been used to provide straightforward spreadsheet based design procedures.............I strongly recommend the book to colleagues in both the academic and industrial sectors." (The Catalyst 2016)