Transport Processes and Separation Process Principles

A. Allen Hersel is currently the associate dean of engineering at Trine University in Angola, Indiana. He is also an associate professor in the department of chemical engineering, where he has taught transport phenomena and separations for the last 12 years. His research is in the area of bioseparations and engineering education. Before entering academia, he worked for Koch Industries and Kellogg Brown & Root. He holds a Ph.D. in chemical engineering from Yale University.   Daniel H. Lepek is a professor in the department of chemical engineering at The Cooper Union. His research interests include particle technology, fluidization and multiphase flow, pharmaceutical engineering, modeling of transport and biotransport phenomena, and engineering education. He is an active member of the American Institute of Chemical Engineers (AIChE), the International Society of Pharmaceutical Engineering (ISPE), and the American Society of Engineering Education (ASEE). He received a bachelor of engineering degree in chemical engineering from The Cooper Union and received his Ph.D. degree in chemical engineering from New Jersey Institute of Technology (NJIT).

Preface to the Fifth Edition xxvii

About the Authors xxxi



 



Part 1: Transport Processes: Momentum, Heat, and Mass

 

Chapter 1: Introduction to Engineering Principles and Units 3



1.0 Chapter Objectives 3

1.1 Classification of Transport Processes and Separation Processes (Unit Operations) 3

1.2 SI System of Basic Units Used in This Text and Other Systems 6

1.3 Methods of Expressing Temperatures and Compositions 8

1.4 Gas Laws and Vapor Pressure 10

1.5 Conservation of Mass and Material Balances 13

1.6 Energy and Heat Units 17

1.7 Conservation of Energy and Heat Balances 23

1.8 Numerical Methods for Integration 28

1.9 Chapter Summary 29

 

Chapter 2: Introduction to Fluids and Fluid Statics 36

2.0 Chapter Objectives 36

2.1 Introduction 36

2.2 Fluid Statics 37

2.3 Chapter Summary 47

 

Chapter 3: Fluid Properties and Fluid Flows 50

3.0 Chapter Objectives 50

3.1 Viscosity of Fluids 50

3.2 Types of Fluid Flow and Reynolds Number 54

3.3 Chapter Summary 58

 

Chapter 4: Overall Mass, Energy, and Momentum Balances 61

4.0 Chapter Objectives 61

4.1 Overall Mass Balance and Continuity Equation 62

4.2 Overall Energy Balance 68

4.3 Overall Momentum Balance 81

4.4 Shell Momentum Balance and Velocity Profile in Laminar Flow 90

4.5 Chapter Summary 96

 

Chapter 5: Incompressible and Compressible Flows in Pipes 105

5.0 Chapter Objectives 105

5.1 Design Equations for Laminar and Turbulent Flow in Pipes 106

5.2 Compressible Flow of Gases 125

5.3 Measuring the Flow of Fluids 129

5.4 Chapter Summary 138

 

Chapter 6: Flows in Packed and Fluidized Beds 145

6.0 Chapter Objectives 145

6.1 Flow Past Immersed Objects 146

6.2 Flow in Packed Beds 150

6.3 Flow in Fluidized Beds 156

6.4 Chapter Summary 161

 

Chapter 7: Pumps, Compressors, and Agitation Equipment 166

7.0 Chapter Objectives 166

7.1 Pumps and Gas-Moving Equipment 166

7.2 Agitation, Mixing of Fluids, and Power Requirements 176

7.3 Chapter Summary 192

 

Chapter 8: Differential Equations of Fluid Flow 196

8.0 Chapter Objectives 196

8.1 Differential Equations of Continuity 196

8.2 Differential Equations of Momentum Transfer or Motion 202

8.3 Use of Differential Equations of Continuity and Motion 207

8.4 Chapter Summary 216

 



Chapter 9: Non-Newtonian Fluids 220



9.0 Chapter Objectives 220

9.1 Non-Newtonian Fluids 221

9.2 Friction Losses for Non-Newtonian Fluids 226

9.3 Velocity Profiles for Non-Newtonian Fluids 229

9.4 Determination of Flow Properties of Non-Newtonian Fluids Using a Rotational Viscometer 232

9.5 Power Requirements in Agitation and Mixing of Non-Newtonian Fluids 234

9.6 Chapter Summary 235

 



Chapter 10: Potential Flow and Creeping Flow 239



10.0 Chapter Objectives 239

10.1 Other Methods for Solution of Differential Equations of Motion 239

10.2 Stream Function 240

10.3 Differential Equations of Motion for Ideal Fluids (Inviscid Flow) 241

10.4 Potential Flow and Velocity Potential 241

10.5 Differential Equations of Motion for Creeping Flow 246

10.6 Chapter Summary 247

 

Chapter 11: Boundary-Layer and Turbulent Flow 250

11.0 Chapter Objectives 250

11.1 Boundary-Layer Flow 251

11.2 Turbulent Flow 254

11.3 Turbulent Boundary-Layer Analysis 260

11.4 Chapter Summary 263

 

Chapter 12: Introduction to Heat Transfer 265

12.0 Chapter Objectives 265

12.1 Energy and Heat Units 265

12.2 Conservation of Energy and Heat Balances 271

12.3 Conduction and Thermal Conductivity 277

12.4 Convection 282

12.5 Radiation 284

12.6 Heat Transfer with Multiple Mechanisms/Materials 287

12.7 Chapter Summary 292

 

Chapter 13: Steady-State Conduction 299

13.0 Chapter Objectives 299

13.1 Conduction Heat Transfer 299

13.2 Conduction Through Solids in Series or Parallel with Convection 305

13.3 Conduction with Internal Heat Generation 313

13.4 Steady-State Conduction in Two Dimensions Using Shape Factors 315

13.5 Numerical Methods for Steady-State Conduction in Two Dimensions 318

13.6 Chapter Summary 326

 

Chapter 14: Principles of Unsteady-State Heat Transfer 332

14.0 Chapter Objectives 332

14.1 Derivation of the Basic Equation 332

14.2 Simplified Case for Systems with Negligible Internal Resistance 334

14.3 Unsteady-State Heat Conduction in Various Geometries 337

14.4 Numerical Finite-Difference Methods for Unsteady-State Conduction 355

14.5 Chilling and Freezing of Food and Biological Materials 366

14.6 Differential Equation of Energy Change 372

14.7 Chapter Summary 376

 

Chapter 15: Introduction to Convection 385

15.0 Chapter Objectives 385

15.1 Introduction and Dimensional Analysis in Heat Transfer 385

15.2 Boundary-Layer Flow and Turbulence in Heat Transfer 389

15.3 Forced Convection Heat Transfer Inside Pipes 394

15.4 Heat Transfer Outside Various Geometries in Forced Convection 402

15.5 Natural Convection Heat Transfer 408

15.6 Boiling and Condensation 415

15.7 Heat Transfer of Non-Newtonian Fluids 424

15.8 Special Heat-Transfer Coefficients 427

15.9 Chapter Summary 436

 

Chapter 16: Heat Exchangers 444

16.0 Chapter Objectives 444

16.1 Types of Exchangers 444

16.2 Log-Mean-Temperature-Difference Correction Factors 447

16.3 Heat-Exchanger Effectiveness 450

16.4 Fouling Factors and Typical Overall U Values 453

16.5 Double-Pipe Heat Exchanger 454

16.6 Chapter Summary 458

 

Chapter 17: Introduction to Radiation Heat Transfer 461

17.0 Chapter Objectives 461

17.1 Introduction to Radiation Heat-Transfer Concepts 461

17.2 Basic and Advanced Radiation Heat-Transfer Principles 465

17.3 Chapter Summary 482

 

Chapter 18: Introduction to Mass Transfer 487

18.0 Chapter Objectives 487

18.1 Introduction to Mass Transfer and Diffusion 487

18.2 Diffusion Coefficient 493

18.3 Convective Mass Transfer 508

18.4 Molecular Diffusion Plus Convection and Chemical Reaction 508

18.5 Chapter Summary 512

 

Chapter 19: Steady-State Mass Transfer 519

19.0 Chapter Objectives 519

19.1 Molecular Diffusion in Gases 519

19.2 Molecular Diffusion in Liquids 528

19.3 Molecular Diffusion in Solids 531

19.4 Diffusion of Gases in Porous Solids and Capillaries 537

19.5 Diffusion in Biological Gels 544

19.6 Special Cases of the General Diffusion Equation at Steady State 546

19.7 Numerical Methods for Steady-State Molecular Diffusion in Two Dimensions 550

19.8 Chapter Summary 557

 

Chapter 20: Unsteady-State Mass Transfer 568

20.0 Chapter Objectives 568

20.1 Unsteady-State Diffusion 568

20.2 Unsteady-State Diffusion and Reaction in a Semi-Infinite Medium 575

20.3 Numerical Methods for Unsteady-State Molecular Diffusion 577

20.4 Chapter Summary 582

 

Chapter 21: Convective Mass Transfer 586

21.0 Chapter Objectives 586

21.1 Convective Mass Transfer 586

21.2 Dimensional Analysis in Mass Transfer 594

21.3 Mass-Transfer Coefficients for Various Geometries 595

21.4 Mass Transfer to Suspensions of Small Particles 610

21.5 Models for Mass-Transfer Coefficients 613

21.6 Chapter Summary 617

 



Part 2: Separation Process Principles

 

Chapter 22: Absorption and Stripping 627



22.0 Chapter Objectives 627

22.1 Equilibrium and Mass Transfer Between Phases 627

22.2 Introduction to Absorption 645

22.3 Pressure Drop and Flooding in Packed Towers 649

22.4 Design of Plate Absorption Towers 654

22.5 Design of Packed Towers for Absorption 656

22.6 Efficiency of Random-Packed and Structured Packed Towers 672

22.7 Absorption of Concentrated Mixtures in Packed Towers 675

22.8 Estimation of Mass-Transfer Coefficients for Packed Towers 679

22.9 Heat Effects and Temperature Variations in Absorption 682

22.10 Chapter Summary 685

 

Chapter 23: Humidification Processes 694

23.0 Chapter Objectives 694

23.1 Vapor Pressure of Water and Humidity 694

23.2 Introduction and Types of Equipment for Humidification 703

23.3 Theory and Calculations for Cooling-Water Towers 704

23.4 Chapter Summary 712

 

Chapter 24: Filtration and Membrane Separation Processes (Liquid–Liquid or Solid–Liquid Phase) 716

24.0 Chapter Objectives 716

24.1 Introduction to Dead-End Filtration 716

24.2 Basic Theory of Filtration 722

24.3 Membrane Separations 732

24.4 Microfiltration Membrane Processes 733

24.5 Ultrafiltration Membrane Processes 734

24.6 Reverse-Osmosis Membrane Processes 738

24.7 Dialysis 747

24.8 Chapter Summary 751

 

Chapter 25: Gaseous Membrane Systems 759

25.0 Chapter Objectives 759

25.1 Gas Permeation 759

25.2 Complete-Mixing Model for Gas Separation by Membranes 765

25.3 Complete-Mixing Model for Multicomponent Mixtures 770

25.4 Cross-Flow Model for Gas Separation by Membranes 773

25.5 Derivation of Equations for Countercurrent and Cocurrent Flow for Gas Separation by Membranes 779

25.6 Derivation of Finite-Difference Numerical Method for Asymmetric Membranes 787

25.7 Chapter Summary 798

 

Chapter 26: Distillation 805

26.0 Chapter Objectives 805

26.1 Equilibrium Relations Between Phases 805

26.2 Single and Multiple Equilibrium Contact Stages 808

26.3 Simple Distillation Methods 813

26.4 Binary Distillation with Reflux Using the McCabe–Thiele and Lewis Methods 818

26.5 Tray Efficiencies 836

26.6 Flooding Velocity and Diameter of Tray Towers Plus Simple Calculations for Reboiler and Condenser Duties 839

26.7 Fractional Distillation Using the Enthalpy–Concentration Method 841

26.8 Distillation of Multicomponent Mixtures 851

26.9 Chapter Summary 862

 

Chapter 27: Liquid–Liquid Extraction 874

27.0 Chapter Objectives 874

27.1 Introduction to Liquid–Liquid Extraction 874

27.2 Single-Stage Equilibrium Extraction 878

27.3 Types of Equipment and Design for Liquid–Liquid Extraction 880

27.4 Continuous Multistage Countercurrent Extraction 889

27.5 Chapter Summary 901

 

Chapter 28: Adsorption and Ion Exchange 907

28.0 Chapter Objectives 907

28.1 Introduction to Adsorption Processes 907

28.2 Batch Adsorption 910

28.3 Design of Fixed-Bed Adsorption Columns 912

28.4 Ion-Exchange Processes 918

28.5 Chapter Summary 924

 

Chapter 29: Crystallization and Particle Size Reduction 928

29.0 Chapter Objectives 928

29.1 Introduction to Crystallization 928

29.2 Crystallization Theory 935

29.3 Mechanical Size Reduction 942

29.4 Chapter Summary 947

 

Chapter 30: Settling, Sedimentation, and Centrifugation 952

30.0 Chapter Objectives 952

30.1 Settling and Sedimentation in Particle–Fluid Separation 953

30.2 Centrifugal Separation Processes 966

30.3 Chapter Summary 979

 

Chapter 31: Leaching 984

31.0 Chapter Objectives 984

31.1 Introduction and Equipment for Liquid–Solid Leaching 984

31.2 Equilibrium Relations and Single-Stage Leaching 990

31.3 Countercurrent Multistage Leaching 994

31.4 Chapter Summary 999

 

Chapter 32: Evaporation 1002

32.0 Chapter Objectives 1002

32.1 Introduction 1002

32.2 Types of Evaporation Equipment and Operation Methods 1004

32.3 Overall Heat-Transfer Coefficients in Evaporators 1008

32.4 Calculation Methods for Single-Effect Evaporators 1010

32.5 Calculation Methods for Multiple-Effect Evaporators 1016

32.6 Condensers for Evaporators 1026

32.7 Evaporation of Biological Materials 1028

32.8 Evaporation Using Vapor Recompression 1029

32.9 Chapter Summary 1030

 

Chapter 33: Drying 1035

33.0 Chapter Objectives 1035

33.1 Introduction and Methods of Drying 1035

33.2 Equipment for Drying 1036

33.3 Vapor Pressure of Water and Humidity 1040

33.4 Equilibrium Moisture Content of Materials 1049

33.5 Rate-of-Drying Curves 1052

33.6 Calculation Methods for a Constant-Rate Drying Period 1057

33.7 Calculation Methods for the Falling-Rate Drying Period 1062

33.8 Combined Convection, Radiation, and Conduction Heat Transfer in the Constant-Rate Period 1065

33.9 Drying in the Falling-Rate Period by Diffusion and Capillary Flow 1068

33.10 Equations for Various Types of Dryers 1074

33.11 Freeze-Drying of Biological Materials 1084

33.12 Unsteady-State Thermal Processing and Sterilization of Biological Materials 1088

33.13 Chapter Summary 1096

 

Part 3: Appendixes

Appendix A.1 Fundamental Constants and Conversion Factors 1107

Appendix A.2 Physical Properties of Water 1113

Appendix A.3 Physical Properties of Inorganic and Organic Compounds 1124

Appendix A.4 Physical Properties of Foods and Biological Materials 1147

Appendix A.5 Properties of Pipes, Tubes, and Screens 1151

Appendix A.6 Lennard-Jones Potentials as Determined from Viscosity Data 1154

 



Notation 1156

Index 1166