Principles of Water Treatment

Preface xv

Acknowledgments xvii

1 Introduction 1

1-1 The Importance of Principles 2

1-2 The Importance of Sustainability 4

References 4

2 Water Quality and Public Health 5

2-1 Relationship between Water Quality and Public Health 5

2-2 Source Waters for Municipal Drinking Water Systems 9

2-3 Regulations of Water Treatment in the United States 17

2-4 Evolving Trends and Challenges in Drinking Water Treatment 21

2-5 Summary and Study Guide 23

References 24

3 Process Selection 25

3-1 Process Selection Based on Contaminant Properties 26

3-2 Other Considerations in Process Selection 30

3-3 Sustainability and Energy Considerations 34

3-4 Design and Selection of Process Trains 39

3-5 Summary and Study Guide 42

Homework Problems 43

References 45

4 Fundamental Principles of Environmental Engineering 47

4-1 Units of Expression for Chemical Concentrations 48

4-2 Chemical Equilibrium 51

4-3 Chemical Kinetics 60

4-4 Reactions Used in Water Treatment 63

4-5 Mass Balance Analysis 66

4-6 Introduction to Reactors and Reactor Analysis 73

4-7 Reactions in Batch Reactors 77

4-8 Hydraulic Characteristics of Ideal Flow Reactors 80

4-9 Reactions in Ideal Flow Reactors 84

4-10 Measuring the Hydraulic Characteristics of Flow Reactors with Tracer Tests 88

4-11 Describing the Hydraulic Performance of Real Flow Reactors 95

4-12 Reactions in Real Flow Reactors 101

4-13 Introduction to Mass Transfer 103

4-14 Molecular Diffusion 104

4-15 Diffusion Coefficients 106

4-16 Models and Correlations for Mass Transfer at an Interface 115

4-17 Evaluating the Concentration Gradient with Operating Diagrams 126

4-18 Summary and Study Guide 131

Homework Problems 133

References 138

5 Coagulation and Flocculation 139

5-1 Role of Coagulation and Flocculation in Water Treatment 140

5-2 Stability of Particles in Water 142

5-3 Principles of Coagulation 149

5-4 Coagulation Practice 150

5-5 Principles of Mixing for Coagulation and Flocculation 162

5-6 Rapid-Mix Practice 163

5-7 Principles of Flocculation 165

5-8 Flocculation Practice 170

5-9 Energy and Sustainability Considerations 186

5-10 Summary and Study Guide 187

Homework Problems 188

References 190

6 Sedimentation 193

6-1 Principles of Discrete (Type I) Particle Settling 196

6-2 Discrete Settling in Ideal Rectangulor Sedimentation Basins 201

6-3 Principles of Flocculant (Type II) Particle Settling 205

6-4 Principles of Hindered (Type III) Settling 206

6-5 Conventional Sedimentation Basin Design 211

6-6 Alternative Sedimentation Processes 220

6-7 Physical Factors Affecting Sedimentation 228

6-8 Energy and Sustainability Considerations 230

6-9 Summary and Study Guide 231

Homework Problems 232

References 234

7 Rapid Granular Filtration 235

7-1 Physical Description of a Rapid Granular Filter 236

7-2 Process Description of Rapid Filtration 242

7-3 Particle Capture in Granular Filtration 246

7-4 Head Loss through a Clean Filter Bed 255

7-5 Modeling of Performance and Optimization 258

7-6 Backwash Hydraulics 266

7-7 Energy and Sustainability Considerations 273

7-8 Summary and Study Guide 274

Homework Problems 275

References 278

8 Membrane Filtration 281

8-1 Classification of Membrane Processes 282

8-2 Comparison to Rapid Granular Filtration 284

8-3 Principal Features of Membrane Filtration Equipment 286

8-4 Process Description of Membrane Filtration 296

8-5 Particle Capture in Membrane Filtration 301

8-6 Hydraulics of Flow through Membrane Filters 305

8-7 Membrane Fouling 309

8-8 Sizing of Membrane Skids 316

8-9 Energy and Sustainability Considerations 319

8-10 Summary and Study Guide 321

Homework Problems 322

References 325

9 Reverse Osmosis 327

9-1 Principal Features of a Reverse Osmosis Facility 329

9-2 Osmotic Pressure and Reverse Osmosis 335

9-3 Mass Transfer of Water and Solutes through RO Membranes 339

9-4 Performance Dependence on Temperature and Pressure 343

9-5 Concentration Polarization 348

9-6 Fouling and Scaling 353

9-7 Element Selection and Membrane Array Design 359

9-8 Energy and Sustainability Considerations 361

9-9 Summary and Study Guide 364

Homework Problems 365

References 368

10 Adsorption and Ion Exchange 369

10-1 Introduction to the Adsorption Process 370

10-2 Adsorption Equilibrium 377

10-3 Adsorption Kinetics 382

10-4 Introduction to the Ion Exchange Process 386

10-5 Ion Exchange Equilibrium 395

10-6 Ion Exchange Kinetics 399

10-7 Fixed-Bed Contactors 400

10-8 Suspended-Media Reactors 423

10-9 Energy and Sustainability Considerations 429

10-10 Summary and Study Guide 430

Homework Problems 431

References 435

11 Air Stripping and Aeration 437

11-1 Types of Air Stripping and Aeration Contactors 438

11-2 Gas-Liquid Equilibrium 443

11-3 Fundamentals of Packed Tower Air Stripping 449

11-4 Design and Analysis of Packed-Tower Air Stripping 459

11-5 Energy and Sustainability Considerations 471

11-6 Summary and Study Guide 472

Homework Problems 473

References 475

12 Advanced Oxidation 477

12-1 Introduction to Advanced Oxidation 479

12-2 Ozonation as an Advanced Oxidation Process 486

12-3 Hydrogen Peroxide/Ozone Process 494

12-4 Hydrogen Peroxide/UV Light Process 505

12-5 Energy and Sustainability Considerations 518

12-6 Summary and Study Guide 519

Homework Problems 520

References 522

13 Disinfection 525

13-1 Disinfection Agents and Systems 526

13-2 Disinfection with Free and Combined Chlorine 532

13-3 Disinfection with Chlorine Dioxide 538

13-4 Disinfection with Ozone 538

13-5 Disinfection with Ultraviolet Light 543

13-6 Disinfection Kinetics 555

13-7 Disinfection Kinetics in Real Flow Reactors 565

13-8 Design of Disinfection Contactors with Low Dispersion 567

13-9 Disinfection By-products 572

13-10 Residual Maintenance 575

13-11 Energy and Sustainability Considerations 576

13-12 Summary and Study Guide 578

Homework Problems 579

References 581

14 Residuals Management 585

14-1 Defining the Problem 586

14-2 Physical, Chemical, and Biological Properties of Residuals 591

14-3 Alum and Iron Coagulation Sludge 595

14-4 Liquid Wastes from Granular Media Filters 599

14-5 Management of Residual Liquid Streams 601

14-6 Management of Residual Sludge 604

14-7 Ultimate Reuse and Disposal of Semisolid Residuals 614

14-8 Summary and Study Guide 616

Homework Problems 617

References 618

Appendix A Conversion Factors 621

Appendix B Physical Properties of Selected Gases and Composition of Air 627

B-1 Density of Air at Other Temperatures 629

B-2 Change in Atmospheric Pressure with Elevation 629

Appendix C Physical Properties of Water 631

Appendix D Periodic Table 633

Appendix E Electronic Resources Available on the John Wiley & Sons Website for This Textbook 635

Index 637