Table of Contents
Preface xix
Acknowledgement xxi
1 Introduction, History, and Applications 1
John R. Grace
1.1 Definition and Origins 1
1.2 Terminology 2
1.3 Applications 3
1.4 Other Reasons for Studying Fluidized Beds 4
1.5 Sources of Information on Fluidization 8
References 8
Problems 9
2 Properties, Minimum Fluidization, and Geldart Groups 11
John R. Grace
2.1 Introduction 11
2.2 Fluid Properties 11
2.3 Individual Particle Properties 12
2.4 Bulk Particle Properties 16
2.5 Minimum Fluidization Velocity 18
2.6 Geldart Powder Classification for Gas Fluidization 24
2.7 Voidage at Minimum Fluidization 27
Solved Problem 28
Notations 28
References 29
Problems 31
3 Liquid Fluidization 33
Renzo Di Felice and Alberto Di Renzo
3.1 Introduction 33
3.2 Field of Existence 33
3.3 Overall Behaviour 35
3.4 Superficial Velocity-Voidage Relationship 37
3.5 Particle Segregation and Mixing 40
3.6 Layer Inversion Phenomena 41
3.7 Heat and Mass Transfer 46
3.8 Distributor Design 48
Solved Problems 48
Notations 51
References 52
Problems 53
4 Gas Fluidization Flow Regimes 55
Xiaotao Bi
4.1 Onset of Fluidization 55
4.2 Onset of Bubbling Fluidization 55
4.3 Onset of Slugging Fluidization 57
4.4 Onset of Turbulent Fluidization 58
4.5 Termination of Turbulent Fluidization 62
4.6 Fast Fluidization and Circulating Fluidized Bed 62
4.7 Flow Regime Diagram for Gas-Solid Fluidized Beds 64
4.8 Generalized Flow Diagram for Gas-Solid Vertical Transport 65
4.9 Effect of Pressure and Temperature on Flow Regime Transitions 68
Solved Problems 70
Notations 71
References 72
Problems 74
5 Experimental Investigation of Fluidized Bed Systems 75
Naoko Ellis
5.1 Introduction 75
5.2 Configuration and Design 76
5.3 Fluidizability and Quality of Fluidization 84
5.4 Instrumentation and Measurements 87
5.5 Operation of Fluidized Beds 93
5.6 Data Analysis 95
Solved Problem 98
Notations 98
References 100
Problems 104
6 Computational Fluid Dynamics and Its Application to Fluidization 109
Tingwen Li and Yupeng Xu
6.1 Two-Fluid Model 110
6.2 Discrete Particle Method 115
6.3 Gas-Solid Interaction 119
6.4 Boundary Conditions 122
6.5 Example and Discussion 123
6.6 Conclusion and Perspective 126
Solved Problem 126
Notations 127
References 128
7 Hydrodynamics of Bubbling Fluidization 131
John R. Grace
7.1 Introduction 131
7.2 Why Bubbles Form 133
7.3 Analogy Between Bubbles in Fluidized Beds and Bubbles in Liquids 134
7.4 Hydrodynamic Properties of Individual Bubbles 135
7.5 Bubble Interactions and Coalescence 139
7.6 Freely Bubbling Beds 139
7.7 Other Factors Influencing Bubbles in Gas-Fluidized Beds 146
Solved Problem 147
Notations 147
References 148
Problems 152
8 Slug Flow 153
John R. Grace
8.1 Introduction 153
8.2 Types of Slug Flow 153
8.3 Analogy Between Slugs in Fluidized Beds and Slugs in Liquids 155
8.4 Experimental Identification of the Slug Flow Regime 155
8.5 Transition to Slug Flow 156
8.6 Properties of Single Slugs 156
8.7 Hydrodynamics of Continuous Slug Flow 158
8.8 Mixing of Solids and Gas in Slugging Beds 159
8.9 Slugging Beds as Chemical Reactors 160
Solved Problem 160
Notations 161
References 161
9 Turbulent Fluidization 163
Xiaotao Bi
9.1 Introduction 163
9.2 Flow Structure 165
9.3 Gas and Solids Mixing 168
9.4 Effect of Column Diameter 172
9.5 Effect of Fines Content 173
Solved Problem 173
Notations 175
References 176
Problems 180
10 Entrainment from Bubbling and Turbulent Beds 181
Farzam Fotovat
10.1 Introduction 181
10.2 Definitions 182
10.3 Ejection of Particles into the Freeboard 184
10.4 Entrainment Beyond the Transport Disengagement Height 185
10.5 Entrainment from Turbulent Fluidized Beds 190
10.6 Parameters Affecting Entrainment of Solid Particles from Fluidized Beds 191
10.7 Possible Means of Reducing Entrainment 195
Solved Problem 195
Notations 196
References 197
Problems 201
11 Standpipes and Return Systems, Separation Devices, and Feeders 203
Ted M. Knowlton and Surya B. Reddy Karri
11.1 Standpipes and Solids Return Systems 203
11.2 Standpipes in Recirculating Solids Systems 212
11.3 Standpipes Used with Nonmechanical Solids Flow Devices 216
11.4 Solids Separation Devices 222
11.5 Solids Flow Control Devices/Feeders 230
Solved Problem 232
Notations 233
References 235
Problems 237
12 Circulating Fluidized Beds 239
Chengxiu Wang and Jesse Zhu
12.1 Introduction 239
12.2 Basic Parameters 241
12.3 Axial Profiles of Solids Holdup/Voidage 243
12.4 Radial Profiles of Solids Distribution 246
12.5 The Circulating Turbulent Fluidized Bed 249
12.6 Micro-flow Structure 250
12.7 Gas and Solids Mixing 256
12.8 Reactor Performance of Circulating Fluidized Beds 258
12.9 Effect of Reactor Diameter on CFB Hydrodynamics 261
Notations 262
References 263
Problems 268
13 Operating Challenges 269
Poupak Mehrani and Andrew Sowinski
13.1 Electrostatics 269
13.2 Agglomeration 273
13.3 Attrition 274
13.4 Wear 278
Solved Problems 280
Notations 286
References 287
Problem 290
14 Heat and Mass Transfer 291
Dening Eric Jia
14.1 Heat Transfer in Fluidized Beds 291
14.2 Mass Transfer in Fluidized Beds 318
Solved Problem 320
Notations 323
References 325
Problem 329
15 Catalytic Fluidized Bed Reactors 333
Andrés Mahecha-Botero
15.1 Introduction 333
15.2 Reactor Design Considerations 334
15.3 Reactor Modelling 334
15.4 Fluidized Bed Catalytic Reactor Models 342
15.5 Conclusions 356
Notations 357
References 358
Problems 361
16 Fluidized Beds for Gas-Solid Reactions 363
Jaber Shabanian and Jamal Chaouki
16.1 Introduction 363
16.2 Gas-Solid Reactions for a Single Particle 364
16.3 Reactions of Solid Particles Alone 377
16.4 Conversion of Particles Bathed by Uniform Gas Composition in a Dense Gas-Solid Fluidized Bed 378
16.5 Conversion of Both Solids and Gas 381
16.6 Thermal Conversion of Solid Fuels in Fluidized Bed Reactors 386
16.7 Final Remarks 390
Solved Problems 391
Acknowledgments 398
Notations 398
References 401
Problems 403
17 Scale-Up of Fluidized Beds 405
Naoko Ellis and Andrés Mahecha-Botero
17.1 Challenges of Scale 405
17.2 Historical Lessons 407
17.3 Influence of Scale on Hydrodynamics 408
17.4 Approaches to Scale-Up 412
17.5 Practical Considerations 415
17.6 Scale-Up and Industrial Considerations of Fluidized Bed Catalytic Reactors 419
Solved Problems 424
Notations 426
References 426
Problems 429
18 Baffles and Aids to Fluidization 431
Yongmin Zhang
18.1 Industrial Motivation 431
18.2 Baffles in Fluidized Beds 432
18.3 Other Aids to Fluidization 449
18.4 Final Remarks 452
Notations 452
References 452
Problem 455
19 Jets in Fluidized Beds 457
Cedric Briens and Jennifer McMillan
19.1 Introduction 457
19.2 Jets at Gas Distributors 457
19.3 Mass Transfer, Heat Transfer, and Reaction in Distributor Jets 467
19.4 Particle Attrition and Tribocharging at Distributor Holes 467
19.5 Jets Formed in Fluidized Bed Grinding 469
19.6 Applications 471
19.7 Jet Penetration 471
19.8 Solids Entrainment into Jets 471
19.9 Nozzle Design 472
19.10 Jet-Target Attrition 473
19.11 Jets Formed When Solids Are Fed into a Fluidized Bed 475
19.12 Jets Formed When Liquid Is Sprayed into a Gas-Fluidized Bed 477
19.13 Jet Penetration 478
Solved Problems 483
Notations 487
References 488
Problem 497
20 Downer Reactors 499
Changning Wu and Yi Cheng
20.1 Downer Reactor: Conception and Characteristics 499
20.2 Hydrodynamics, Mixing, and Heat Transfer of Gas-Solid Flow in Downers 501
20.3 Modelling of Hydrodynamics and Reacting Flows in Downers 508
20.4 Design and Applications of Downer Reactors 514
20.5 Conclusions and Outlook 523
Solved Problem 523
Notations 525
References 526
Problems 528
21 Spouted (and Spout-Fluid) Beds 531
Norman Epstein
21.1 Introduction 531
21.2 Hydrodynamics 532
21.3 Heat and Mass Transfer 538
21.4 Chemical Reaction 538
21.5 Spouting vs. Fluidization 539
21.6 Spout-Fluid Beds 540
21.7 Non-conventional Spouted Beds 543
21.8 Applications 546
21.9 Multiphase Computational Fluid Dynamics 547
Solved Problem 547
Notations 548
References 549
22 Three-Phase (Gas-Liquid-Solid) Fluidization 553
Dominic Pjontek, Adam Donaldson, and Arturo Macchi
22.1 Introduction 553
22.2 Reactor Design and Scale-up 556
22.3 Compartmental Flow Models 558
22.4 Fluid Dynamics in Three-Phase Fluidized Beds 562
22.5 Phase Mixing, Mass Transfer, and Heat Transfer 569
22.6 Summary 574
Solved Problems 574
Notations 582
References 585
Problems 587
Index 591
