Handbook of fluidization and fluid-particle systems

HANDBOOK of FLUIDIZATION and FLUID-PARTICLE SYSTEMS......Page 2
Table of Contents......Page 9
CHEMICAL INDUSTRIES, A Series of Reference Books and Textbooks......Page 4
Preface......Page 7
Contributors......Page 11
Volume Diameter......Page 13
Martin Diameter......Page 14
Circularity......Page 15
Operational Sphericity and Circularity......Page 16
The Heywood Shape Factor......Page 17
2 PARTICLE CHARACTERIZATION TECHNIQUES......Page 18
Martin diameter......Page 19
2.1.3 Gravity and Centrifugal Sedimentation......Page 20
2.1.6 Resistivity and Optical Zone Sensing Techniques......Page 22
2.2 Effect of Particle Shape on Size Distribution Measured with Commercial Equipment......Page 24
2.3.2 Attrition Index......Page 25
3.1 Definition of Particle Drag Coefficient......Page 26
3.2. The Stokes Law Regime......Page 27
3.6 Empirical Drag Coefficient Expression......Page 28
3.7 Corrections for Nonspherical Particles......Page 29
4.1 Equation by Haider and Levenspiel (1989)......Page 30
4.2 Terminal Velocity by Polynomial Equations Fitted to Heywood Tables......Page 31
4.3 Calculation of Terminal Velocity of Porous Spheres......Page 32
5.1.6 Length Mean......Page 33
5.2 Statistical Characterization of Particles with a Size Distribution......Page 34
5.4 Measurement of the Angle of Repose and the Angle of Internal Friction......Page 36
NOMENCLATURE......Page 37
REFERENCES......Page 38
1.2 Random Packing of Uniform Monosize Spheres......Page 40
1.4 Specific Surface Area of the Bed......Page 42
2 PACKING CHARACTERISTICS OF BINARY MIXTURES OF SPHERICAL AND NONSPHERICAL PARTICLES......Page 43
3 CRITICAL RATIO OF ENTRANCE AND CRITICAL RATIO OF OCCUPATION IN BINARY SYSTEMS......Page 45
4 PACKING OF NON-SPHERICAL PARTICLES......Page 46
5 FACTORS AFFECTING PACKING DENSITY IN PRACTICE......Page 47
6 CORRELATIONS FOR FIXED BED BULK VOIDAGE......Page 48
7.1 Darcy’s Law......Page 50
7.2 Blake’s Correlation......Page 51
7.3 The Brownell and Kats Correlation......Page 52
7.5.1 Use of Ergun Equation to Determine Sphericity Factor......Page 53
7.9 The General Correlation by Barnea and Mednick......Page 54
7.11 Permeability of Packed Beds......Page 55
8 GAS VELOCITY DISTRIBUTION IN PACKED BEDS......Page 56
9.1.3 Wall Heat Transfer Coefficient—Two- Dimensional......Page 57
9.3 Analytical Models for Heat Transfer with Immersed Surfaces......Page 58
NOMENCLATURE......Page 60
REFERENCES......Page 62
1 INTRODUCTION......Page 64
2.2 Molerus’ Interpretation of Geldart’s Classification of Powders......Page 65
2.4 Goossen’s Classification of Particles by Archimedes Number......Page 66
2.5.1 Bubble Escaping Stage, 0 < t < tb......Page 67
3 DIFFERENT REGIMES OF FLUIDIZATION......Page 68
3.1 Transition among Fixed Bed, Particulate Fluidization, and Bubbling Regime......Page 69
3.3 Transition Between Bubbling and Turbulent Regimes......Page 70
3.4 Transition to Fast Fluidization......Page 72
4 THEORETICAL AND EMPIRICAL PREDICTIONS OF MINIMUM FLUIDIZATION VELOCITY......Page 73
6 TWO-PHASE THEORY OF FLUIDIZATION......Page 75
7 VISCOSITY OF A FLUIDIZED BED......Page 76
9 BUBBLE PHASE IN FLUIDIZED BEDS......Page 78
9.2 Bubbles in Gas–Solid Fluidized Beds......Page 79
9.3 Davidson’s Isolated Bubble Model......Page 80
9.3.2 Slow Bubbles Regime—When UB < Umf=emf......Page 81
9.4 Bubble Formation in a Fluidized Bed......Page 82
9.5 Coalescence of Bubbles in Fluidized Beds......Page 83
9.5.1 Bubble Coalescence from Mutiple Entry Nozzles......Page 85
10 SLUGGING BEDS......Page 86
10.3 Slug Length and Slug Frequency......Page 87
10.4 Minimum Bed Height Required for Slugging......Page 88
11 JETTING PHENOMENA IN FLUIDIZED BEDS......Page 89
11.1 Different Jetting Regimes Observed in Fluidized Beds......Page 91
11.2.3 Jet Penetration Depth......Page 92
11.3 Initial Bubble Size and Frequency......Page 95
11.5 Gas and Solids Entrainment......Page 96
11.6 Interacting Jets in Fluidized Beds......Page 97
12 PARTICLE MIXING AND SEGREGATION IN A GAS FLUIDIZED BED......Page 98
12.1 Particle Mixing in a Gas Fluidized Bed......Page 100
12.1.2 Convective Solids Transport and Mixing......Page 101
12.1.3 Bed Turnover Time......Page 102
12.2 Particle Segregation in a Gas Fluidized Bed......Page 103
12.2.1 Analogy to Gas–Liquid–Solid Phase Equilibrium......Page 104
12.2.3 Minimum Fluidization Velocity of a Binary Mixture......Page 105
12.2.4 Minimum Fluidization Velocity of a Multicomponent Mixture......Page 107
12.2.6 Effect of Particle Size, Density, Shape, and Gas Velocity......Page 108
Rate of Particle Separation in Batch Systems......Page 110
Continuous Operation and Industrial Applications......Page 113
12.3 Mathematical Models for Prediction of Equilibrium Concentration Profiles......Page 114
NOMENCLATURE......Page 115
REFERENCES......Page 117
2 DEFINITIONS......Page 123
3 EJECTION OF PARTICLES INTO THE FREEBOARD......Page 124
4 GAS–SOLIDS FLOW IN THE FREEBOARD......Page 125
5.1 Influence of Particle Size......Page 126
5.3.2 Effect of Diameter......Page 128
5.6 Influence of Temperature and Pressure......Page 129
6.1 Entrainment for Freeboard Heights Exceeding TDH......Page 130
6.2 Estimation of TDH......Page 131
6.3 Entrainment for Freeboard Heights Below TDH......Page 134
NOMENCLATURE......Page 135
REFERENCES......Page 136
2 MINIMUM FLUIDIZATION VELOCITY......Page 139
3 TERMINAL FALL VELOCITY OF SINGLE PARTICLES......Page 142
4.1.1 Group A Powders......Page 143
4.1.2 Group B Powders......Page 144
4.2 Temperature......Page 150
5 JET PENETRATION......Page 151
6.2 Temperature and Pressure Effects......Page 152
6.3 Entrainment and Elutriation......Page 153
7.1 Bubbling Beds......Page 154
7.2 Circulating Beds......Page 156
7.3 Application of Dimensional Analysis......Page 157
8 SINTERING AND AGGLOMERATION......Page 158
Subscripts......Page 160
REFERENCES......Page 161
Main Advantages......Page 165
Possible Disadvantages......Page 166
3.1 Jet Penetration......Page 167
3.2 Grid Pressure Drop Criteria......Page 168
3.3 Design Equations......Page 169
3.4 Additional Criteria for Sparger Grids......Page 170
5.1 Erosion at Bed Walls and Internals......Page 171
5.2 Erosion at Distributor Nozzles......Page 172
6 WEEPAGE OF SOLIDS......Page 173
8 PLENUM DESIGN......Page 174
9 POWER CONSUMPTION......Page 175
10.1 FCC Grid Design......Page 176
10.2 Polyethylene Reactor Grid Design......Page 178
NOMENCLATURE......Page 179
REFERENCES......Page 180
1 INHERENT FLOW STRUCTURES OF GAS– SOLID FLOW......Page 181
1.1 Flow Structure of Bubbling Fluidization......Page 182
1.2 Flow Structure of Turbulent Fluidization......Page 183
1.3 Flow Structure of Fast Fluidization......Page 184
2.1 Baffles......Page 185
2.2 Tubes......Page 190
2.3 Packings......Page 192
2.4 Insert Bodies......Page 194
2.5 Other Configurations......Page 196
3.1 Bubble Behavior......Page 199
3.2 Flow Distribution......Page 203
3.3 Gas and Solids Mixing......Page 204
3.4 Transition to Turbulent Fluidization......Page 205
REFERENCE......Page 207
1 INTRODUCTION......Page 210
2 THE MODES OF ATTRITION AND THE FACTORS AFFECTING THEM......Page 211
2.1.4 Particle Shape and Surface Structure......Page 213
2.1.5 Pretreatment and Preparation or Processing History......Page 214
2.2.3 Solids Residence Time......Page 216
2.2.6 Chemical Reaction......Page 217
3.2 Assessment of the Attrition-Induced Material Loss......Page 218
3.3 Assessment of Changes in the Particle Size Distribution......Page 219
4.2 Experiments to Study Attrition Mechanisms......Page 221
4.3.1 Tests Applying Well-Defined Stress......Page 222
4.3.3 Fluidized Bed Tests......Page 223
4.3.4 Cyclone Tests......Page 225
5.SOURCES OF ATTRITION IN A FLUIDIZED BED SYSTEM......Page 227
5.1 Grid Jet as a Source of Attrition......Page 228
5.2 Bubble-Induced Attrition......Page 230
5.3 Cyclones as Attrition Sources......Page 231
6 ATTRITION IN THE OVERALL FLUIDIZED BED SYSTEM......Page 233
6.2 Changes in the Bed Particle Size Distribution......Page 237
NOMENCLATURE......Page 242
REFERENCES......Page 243
2 PSEUDOHOMOGENEOUS MODELS......Page 247
3 TWO-PHASE MODELS......Page 248
3.1.1 Model of Davidson and Harrison (1963)......Page 249
3.2.1 Derivation of the Model......Page 252
3.2.2 Model Expression for First-Order Kinetics......Page 253
3.3 Bubble Assemblage Model......Page 254
3.3.1 Key Equations in the Bubble Assemblage Model......Page 255
3.3.2 Calculation Procedure Based on Bubble Assemblage Model......Page 256
3.3.4 Discussion of the Bubble Assemblage Model......Page 257
4 MULTIPLE-REGION MODELS......Page 258
4.2 Models for the Freeboard Region......Page 259
NOTATION......Page 260
REFERENCES......Page 262
1 INTRODUCTION......Page 264
2.1 Hydrodynamics......Page 265
2.2.1 Particle Gas Transfer......Page 266
Convective Heat Transfer.......Page 268
Radiative Heat Transfer.......Page 272
Freeboard Heat Transfer.......Page 273
3.1 Hydrodynamics......Page 275
3.2.2 Bed–Surface Transfer......Page 276
Convective Heat Transfer.......Page 277
4.1 Bubbling Fluidized Bed......Page 280
4.1.1 Fluidization Regime......Page 281
4.1.3 Bed-to-Tube Heat Transfer......Page 282
4.1.4 Heat Transfer Coefficient from Packet Model......Page 283
4.1.5 Heat Transfer Coefficient from Kinetic......Page 284
4.2 Fast Fluidized Bed......Page 285
4.2.2 Convective Heat Transfer at the Wall......Page 286
4.2.3 Convective Coefficient Calculated from Pressure Drop......Page 287
4.2.4 Convective Coefficient from Surface Renewal Model......Page 288
4.2.5 Heat Transfer in a High-Temperature Bed......Page 289
Greek Symbols......Page 290
REFERENCES......Page 291
2 HOMOGENEOUS BED APPROACH......Page 294
2.2 Transfer Between Fixed Bed Particles and Flowing Gas......Page 295
(a) For large particles (>1mm),......Page 296
(b) For intermediate particles (40 mm < dp <1mm),......Page 297
2.3 Transfer Between Fluidized Bed Particles and Fluidizing Gas......Page 298
2.3.1 Average Mass Transfer Coefficient, k,bed......Page 299
2.4 Transfer Between Immersed Isolated Spheres and a Fluidized Bed......Page 300
3 BUBBLING BED APPROACH......Page 301
3.1.1 Relation Between KGB and kg,bed A......Page 302
3.1.2 KGB for Nonporous and Nonadsorbing Particles......Page 304
3.2 Model of Partridge and Rowe (1966)......Page 305
3.3 Model of Chavarie and Grace (1976a)......Page 306
3.4 Mass Transfer in the Grid Region......Page 308
4 RELATION BETWEEN MASS AND HEAT TRANSFER COEFFICIENTS......Page 309
6.1 Example 1 Effect of db on Shbed based on Eq.(61)......Page 310
NOMENCLATURE......Page 311
REFERENCES......Page 313
1 INTRODUCTION......Page 315
1.1 Features and Commercial Processes of Fluidized Bed Reactors......Page 316
1.2 General Procedure for the Development of Fluidized Bed Reaction Processes......Page 319
2.1 Particle Selection and Catalyst Development......Page 321
2.2 Flow Regime Relevancy......Page 323
2.2.1 Characteristics of Flow Regimes......Page 324
2.2.2 Gas–Solid Contact and Interphase Mass Transfer......Page 325
2.2.3 Solids Mixing......Page 327
2.2.5 Heat Transfer......Page 328
2.2.6 Flow Regime Selection......Page 329
2.3.1 Catalytic Reactions......Page 332
2.3.2 Gas–Solid Reactions......Page 333
2.3.3 Gas-Phase Olefin Polymerization......Page 334
2.3.4 Physical Operations......Page 337
3 REACTOR MODELING AND ESTIMATION OF DESIGN PARAMETERS......Page 338
3.1 Bubbling Fluidized Bed Reactors......Page 339
3.2 Turbulent Fluidized Bed Reactors......Page 340
3.3 Riser and Downer Reactors......Page 341
4 CONCLUSION......Page 345
NOTATION......Page 346
REFERENCES......Page 347
1 INTRODUCTION......Page 349
2 REACTOR MODELING: BED DIAMETER INFLUENCE......Page 351
3.1 Bubbling Beds......Page 353
3.2 Mixing......Page 355
3.3 Influence of Bed Diameter on Circulating or Fast Fluidized Beds......Page 356
3.4 Flow Transition......Page 358
4.1 Development of Scaling Parameters......Page 359
5.1 Range of Validity of Simplified Scaling......Page 361
5.2 Clusters......Page 362
7.1 Full Set of Scaling Relationships......Page 364
7.2 Design of Scale Models Using the Simplified Set of Scaling Relationships......Page 366
7.3 Hydrodynamic Scaling of Bubbling Beds......Page 368
7.4 Verification of Scaling Relationships for Bubbling and Slugging Beds......Page 369
7.5 Verification of Scaling Laws for Spouting Beds......Page 371
7.6 Verification of Scaling Relationships for Pressurized Bubbling Beds......Page 372
8 APPLICATIONS OF SCALING TO COMMERCIAL BUBBLING FLUIDIZED BED UNITS......Page 373
9 HYDRODYNAMIC SCALING OF CIRCULATING BEDS......Page 375
NOTATION......Page 381
REFERENCES......Page 382
1.2 How the FCC Unit Fits in a Typical US Refinery......Page 385
1.4 Why Is Particulate Technology Important to FCC?......Page 386
2.2 Catalytic Cracking Reactions......Page 387
2.3 Thermal Cracking Reactions......Page 388
2.4 Heat Balance......Page 389
2.5 Pressure Balance and Catalyst Circulation......Page 390
3.1 Feed Injection System......Page 391
3.2 Riser/Reactor......Page 395
3.4 Regenerator......Page 396
3.6 Standpipe and Standpipe Inlet......Page 399
REFERENCES......Page 401
1 INTRODUCTION......Page 403
2.1.2 Functions and Requirements......Page 404
2.1.3 Reaction Environment......Page 405
2.2 Status of Fluidized Bed Gasifier Technology......Page 406
2.3.1 Gasification of Coal......Page 412
2.3.2 Gasification of Biomass Fuels......Page 414
3.1 Fluidized Bed Combustor Principles......Page 415
3.3 Fluidized Bed Combustor Design Considerations......Page 418
3.3.1 Coal Fueled AFBC......Page 419
3.3.3 Coal Fueled PFBC......Page 422
REFERENCES......Page 424
1.1 Acrylonitrile......Page 427
1.2 Maleic Anhydride......Page 428
1.4 Phthalic Anhydride......Page 431
2.1 Sasol......Page 434
2.2 Exxon......Page 436
2.3 Syntroleum......Page 437
3 POLYMERIZATION OF OLEFINS......Page 438
4.1 Fluid Coking......Page 440
4.4 Combi-Cracking......Page 441
5 SEMICONDUCTOR SILICON......Page 443
6.3 Ore Roasting......Page 444
7.1 UOP/Hydro Methanol to Olefins......Page 445
7.2 Mobil–Badger Technologies......Page 446
7.3 Catalytic Oxidation of Chlorinated Byproducts......Page 447
7.4 Isophthalonitrile......Page 448
REFERENCES......Page 449
1 SUMMARY......Page 451
2. THE FLUID BED AS A MIXER/ GRANULATOR......Page 452
3 MICROSCOPIC PHENOMENA......Page 455
4.1 Critical Binder (Liquid)/Powder Ratio......Page 456
4.2 Binder and Interparticle Bridge Properties......Page 457
5.1 Conditions of Coalescence......Page 458
5.2 Prediction of Critical Sizes......Page 459
5.4 Summary of Growth and Deformation Kinetics......Page 460
7.1 Granulation in a Constant Shear Fluidized Bed......Page 462
7.2.2 Agglomerate Growth......Page 464
7.2.3 Agglomerate Consolidation......Page 466
7.3 Experimental Data by Dencs and Ormos (1993, 1994)......Page 467
8.1 Simulation of Granule Growth by Coalescence......Page 469
8.2 Simulation of Granule Deformation and Breakup......Page 471
CONCLUSIONS......Page 472
Subscripts and Superscripts......Page 473
REFERENCES......Page 474
1 INTRODUCTION......Page 475
2 CLASSIFICATION AND SELECTION CRITERIA......Page 476
3 BASICS OF DRYING KINETICS......Page 479
3.1 Effect of Bed Height......Page 480
4.4 Vibrated Fluidized Bed Dryers (VFBDs)......Page 481
4.7 Spouted Bed Dryers (SBDs)......Page 482
5.1 A Simple Calculation Method for Batch Drying in a Fluidized Bed Dryer......Page 483
5.2 Predicting the Performance of a Continuous Fluidized Bed Dryer from Batch Drying Data......Page 485
6.1 Modified Fluidized Bed Dryers......Page 486
6.2 Superheated Steam Drying in Fluidized Beds......Page 487
CLOSING REMARKS......Page 488
REFERENCES......Page 489
1 INTRODUCTION......Page 491
3.1.1 Transport Velocity, Utr, based on Phase Diagrams......Page 492
3.1.2 Critical Velocity, Use, Based on Solids Entrainment......Page 493
3.2.2 Transition from Fast Fluidization to Dense Suspension Upflow......Page 494
3.3 Flow Regime and Operating Diagrams......Page 495
Optical Probes......Page 496
Capacitance Probes......Page 497
4.1.2 Axial Voidage/Solids Holdup Profiles......Page 498
4.1.3 Radial/Lateral Voidage/Solids Holdup Profiles......Page 501
4.2.1 Measurement Techniques......Page 502
4.2.2 Experimental Results......Page 503
4.3.1 Net Solids Circulation Flux......Page 504
4.3.3 Radial Profiles of Solids Flux......Page 505
4.3.4 Wall or Annular Layer Thickness......Page 506
4.5.1 Inflluence of Cross Section Shape: Circular vs. Rectangular......Page 507
4.5.3 Influence of Bottom Configuration......Page 508
4.5.5 Exit Effects......Page 509
4.5.8 Geometric Variants......Page 510
4.6.2 Mechanistic Models......Page 511
4.7 Scale-Up Considerations......Page 512
5.2 High-Density Circulating Fluidized Beds......Page 514
6.1 Gas Mixing......Page 515
6.1.1 Gas RTD and Effective Gas Dispersion......Page 516
6.1.2 Radial Gas Dispersion......Page 517
6.1.3 Gas Backmixing......Page 518
6.1.5 Interphase Mass Transfer......Page 519
6.2.1 Axial Dispersion of Particles......Page 520
6.2.3 Interphase Solids Exchange Between Core and Annulus......Page 521
7.2 Convection......Page 522
Heat Transfer Surface:......Page 523
Bulk Suspension Temperature:......Page 524
Emulsion Models:......Page 525
Non uniform Emulsion Models:......Page 526
7.4 Recommended Method for Estimating Total Heat Transfer......Page 527
8 MASS TRANSFER......Page 529
9.1 Introduction and Key Considerations......Page 530
9.2 One-Dimensional Models......Page 532
9.3 Core–Annulus Models......Page 533
9.4 More Sophisticated Models......Page 535
NOMENCLATURE......Page 536
REFERENCES......Page 538
2 SPOUTED BED......Page 551
2.1 Minimum Spouting Velocity......Page 552
2.3 Spout Diameter......Page 553
2.6 Particle Movement and Fountain Height......Page 554
2.8.2 Bed Voidage Along the Spout Axis......Page 555
3 RECIRCULATING FLUIDIZED BEDS WITH A DRAFT TUBE......Page 556
3.1 Draft Tube Operated as a Fluidized Bed......Page 557
Draft Tube Pressure Drop......Page 558
3.2.3 Solids Circulation Mechanisms and the Solids Circulation Rate......Page 559
3.3 Design Procedure for a Recirculating Fluidized Bed with a Draft Tube......Page 560
3.6 Industrial Applications......Page 561
4.1 Jet Penetration and Bubble Dynamics......Page 562
4.1.3 Bubble Dynamics......Page 563
4.2.1 Gas Mixing Around Single Jets......Page 564
4.3.1 Solids Circulation Pattern......Page 565
4.3.2 Solids Circulation Rate......Page 567
4.4 Solid Entrainment Rate into Gas and Gas–Solid Two-Phase Jets......Page 568
5 ROTATING FLUIDIZED BEDS......Page 569
5.1 Minimum Fluidization Velocity......Page 570
NOTATION......Page 571
Greek Letters......Page 572
REFERENCES......Page 573
2 STANDPIPES......Page 577
2. Fluidized Bed Flow.......Page 579
3. Streaming Flow.......Page 580
2.2 Standpipes in Recirculating Solid Systems......Page 587
2.4 Controlled Solid Recirculation Systems......Page 588
2. They are inexpensive......Page 591
2.6 Nonmechanical Valve Mode Operation......Page 592
2.7.1 Seal Pot......Page 597
2.7.4 V-Valve......Page 598
2.7.5 L-valve......Page 599
2.7.6 Cyclone Diplegs and Trickle Valves......Page 600
NOMENCLATURE......Page 602
REFERENCES......Page 603
2 CYCLONES......Page 604
2.1 Cyclone Types......Page 605
2.2 Flow Patterns in Cyclones......Page 606
3.1 Series......Page 607
3.2 Parallel......Page 608
5 CYCLONE INLET DESIGN......Page 609
6 EFFECT OF SOLIDS LOADING......Page 610
7 GAS OUTLET TUBE......Page 611
8 INLET GAS VELOCITY......Page 612
11 CYCLONE DIAMETER......Page 613
12 CYCLONE DIMENSIONS AND DESIGN......Page 614
12.1.3 Calculate dpi=Dp;th and Determine Eoi......Page 615
12.1.5 Calculate Cyclone Pressure Drop......Page 616
5. Outlet Exit Contraction Pressure Drop.......Page 617
13 VORTEX LENGTH......Page 618
14 EFFECT OF PRESSURE AND TEMPERATURE......Page 620
NOMENCLATURE......Page 621
REFERENCES......Page 622
1 INTRODUCTION......Page 623
2.3 Force Balance......Page 624
2.6 Friction Factors......Page 625
2.10 Compressibility......Page 626
2.12 Choking Conditions......Page 627
3 FLOW CLASSIFICATIONS......Page 628
4.4 Filters......Page 630
5 TROUBLESHOOTING......Page 631
7 APPLICATIONS OF COMPUTER ANALYSIS......Page 632
REFERENCES......Page 633
2 PNEUMATIC CONVEYING AND CHARGING......Page 634
3 USEFULNESS OF ELECTROSTATICS......Page 635
4 PRECAUTIONS......Page 636
5.1 Horizontal System......Page 637
5.3 Electrostatics with Small Glass Beads......Page 638
5.4 Electrostatics with Larger Glass Beads......Page 640
NOMENCLATURE......Page 642
REFERENCES......Page 643
1 INTRODUCTION......Page 645
2.1.2 Optical Pyrometer......Page 646
2.1.3 Infrared Camera/Thermometer......Page 648
2.3.1 Gas Pressure......Page 649
2.3.3 Solid Pressure......Page 651
2.4.1 Fundamentals of Light Measurement......Page 652
2.4.2 Light Sources......Page 653
2.4.4 Optical Fibers......Page 654
2.4.5 Optical Fiber Probe......Page 655
2.4.6 LDV—Laser Doppler Velocimetry......Page 657
2.4.7 Space Filters......Page 664
2.6.1 Microphones......Page 666
2.8 Gas Sensors......Page 668
2.10 Radioactive Sensors......Page 669
2.12 Suction Probes for Solids Sampling......Page 670
3.1 Data Processing......Page 673
3.1.1 Autocorrelation......Page 674
3.1.3 Power Spectrum......Page 677
3.1.5 Wavelet Transform......Page 678
3.2.2 Laser Imaging......Page 681
3.3.1 Image Reconstruction Principle......Page 683
3.4 On-Line Particle Size Distribution Measurement......Page 686
4 FLUIDIZED BED DIAGNOSTICS......Page 687
4.1.3 Bubble Fraction and Visible Bubble Flow Distribution......Page 689
4.1.4 Bubble Size Calculation from Pierced Length......Page 690
4.2.2 Solid Circulation Rate......Page 692
4.3.1 Minimum Fluidization Velocity......Page 693
4.3.4 Regime Transition Velocities......Page 694
5 SUMMARY......Page 695
REFERENCES......Page 696
2.1 Introduction......Page 707
2.2 Buoyancy and Drag......Page 708
2.2 Hydrodynamic Representation......Page 709
3 MINIMUM FLUIDIZATION......Page 711
4.1 Introduction......Page 714
4.2 Theoretical Models......Page 715
4.3 Empirical Equations......Page 717
5.1 Deductions from Pressure Gradient Measurements......Page 723
5.2 Binary Mixtures—Overview......Page 724
5.3 Binary Mixtures of Equal Density Particles......Page 725
5.4 Binary Mixtures of Equal Size Particles......Page 728
5.5 Binary Mixtures of Particles Differing in Size and Density: Bed Inversion......Page 729
6 INVERSE FLUIDIZATION......Page 732
7.2 Multidisperse Solids......Page 733
8.1 Axial Dispersion......Page 736
9 NONHOMOGENEITIES AND INSTABILITY......Page 737
10 DISTRIBUTOR DESIGN......Page 739
11 MASS (AND HEAT) TRANSFER BETWEEN PARTICLES AND LIQUID......Page 740
12.1 Heat Transfer......Page 742
12.2 Mass Transfer......Page 744
13 APPLICATIONS (as abridged by Wen-Ching Yang)......Page 745
In-situ fluidized washing......Page 746
Leaching,......Page 747
Fluidized bed electrodes,......Page 748
Liquid-fluidized bed heat exchangers......Page 749
Fluidized bed bioreactors......Page 750
NOMENCLATURE......Page 752
REFERENCES......Page 755
1 INTRODUCTION......Page 767
2.1 Plenum Bubble Behavior......Page 768
2.2 Bubble Rise Characteristics......Page 772
2.2.1 Single Bubble Rise Velocity in Liquids......Page 773
2.2.2 Single Bubble Rise Velocity in Liquid–Solid Suspensions......Page 775
2.3 Bubble Coalescence......Page 776
2.4 Bubble Breakup......Page 777
3.1.1 Minimum Fluidization......Page 780
3.1.2.1 Bed Contraction.......Page 781
3.1.3 Flow Regime Transition......Page 782
3.1.4 Overall Gas Holdup and Hydrodynamic Similarity......Page 783
3.1.5 Bubble Size Distribution and Dominant Role of Large Bubbles......Page 785
3.2 Heat Transfer......Page 786
3.2.2 Bubble Wake Effect......Page 787
3.2.3 Pressure Effect......Page 788
3.3 Mass Transfer......Page 790
3.3.2 Liquid-Phase Mass Transfer Coefficient......Page 791
3.4 Phase Mixing......Page 793
4 COMPUTATIONAL FLUID DYNAMICS......Page 796
4.1 Liquid-Phase Model......Page 797
4.3 Discrete Particle Method......Page 798
4.4.1 Liquid Shear Effect......Page 799
4.5 Simulation Examples......Page 800
5 SUMMARY......Page 802
NOMENCLATURE......Page 804
Greek Letters......Page 805
REFERENCES......Page 806
1.1.1 Aqueous Systems......Page 812
2.1 Cake Filtration......Page 813
2.1.1 Cake Filtration Equation—Two Resistance Model......Page 814
2.2.2 Pressure Drop in Deep-Bed Filtration......Page 815
2.3.2 Microfiltration......Page 816
2.4 Filter Media......Page 817
2.5.1 Requirements for Filter Aid Selection......Page 820
2.5.2 Filtration with Filter Aids......Page 821
Horizontal Filters.......Page 822
2.6.2 Deep-Bed Filtration Units......Page 824
NOMENCLATURE......Page 825
Greek Symbols......Page 826
REFERENCES......Page 827
3.1 Sedimentation Fundamentals......Page 828
Thickener Basin Depth.......Page 829
Torque Requirement.......Page 830
3.2.2 Thickener Types and Selection......Page 831
3.3 Clarifiers......Page 832
3.3.1 Clarifier Design......Page 833
3.3.2 Clarifier Types and Selection......Page 835
NOMENCLATURE......Page 836
4.1.1 Principles of Sedimentation Centrifuges......Page 837
4.1.2 Major Types of Sedimentation Centrifuges......Page 838
4.2.2 Major Types of Filter Centrifuges......Page 840
Basket Centrifuges......Page 841
Pusher Centrifuges.......Page 842
Conical Screen Filter Centrifuges......Page 844
5.1.1 Total Efficiency......Page 845
5.1.3 Grade Efficiency......Page 846
5.2.2 Particle Motion in Hydrocyclones......Page 847
Equilibrium Orbit Theory.......Page 848
5.3.2 Design Variables......Page 849
5.4 Design and Scale-Up......Page 850
REFERENCES......Page 851