Beginning with the generic means for investigating water to complex processes for the removal of soluble and particulate materials, Water Quality Engineering: Physical/Chemical Treatment Processes provides a comprehensive overview of the physical and chemical processes for treating water and wastewater. Author M. Benjamin describes the fundamental and mathematical theory behind water treatment methods and includes examples illustrating common calculations related to each process, as well as more concrete, real-world examples in each chapter. The text provides a theoretical underpinning of practice, making it a valuable reference for working environmental engineers.
PREFACE xxi
ACKNOWLEDGMENTS xxv
PART I REACTORS AND REACTIONS INWATER QUALITY ENGINEERING
1 Mass Balances 3
1.1 Introduction: The Mass Balance Concept, 3
1.2 The Mass Balance for a System with Unidirectional Flow and Concentration Gradient, 7
1.3 The Mass Balance for a System with Flow and Concentration Gradients in Arbitrary Directions, 20
1.4 The Differential Form of the Three-Dimensional Mass Balance, 24
1.5 Summary, 25
2 Continuous Flow Reactors: Hydraulic Characteristics 29
2.1 Introduction, 29
2.2 Residence Time Distributions, 30
2.3 Ideal Reactors, 42
2.4 Nonideal Reactors, 48
2.5 Equalization, 62
2.6 Summary, 70
3 Reaction Kinetics 81
3.1 Introduction, 81
3.2 Fundamentals, 82
3.3 Kinetics of Irreversible Reactions, 88
3.4 Kinetics of Reversible Reactions, 99
3.5 Kinetics of Sequential Reactions, 107
3.6 The Temperature Dependence of the Rates of Nonelementary Reactions, 114
3.7 Summary, 115
4 Continuous Flow Reactors: Performance Characteristics with Reaction 121
4.1 Introduction, 121
4.2 Extent of Reaction in Single Ideal Reactors at Steady State, 121
4.3 Extent of Reaction in Systems Composed of Multiple Ideal Reactors at Steady State, 130
4.4 Extent of Reaction in Reactors with Nonideal Flow, 135
4.5 Extent of Reaction Under Non-Steady-Conditions in Continuous Flow Reactors, 141
4.6 Summary, 146
PART II REMOVAL OF DISSOLVED CONSTITUENTS FROM WATER
5 Gas Transfer Fundamentals 155
5.1 Introduction, 155
5.2 Types of Engineered Gas Transfer Systems, 159
5.3 Henry’s Law and Gas/Liquid Equilibrium, 162
5.4 Relating Changes in the Gas and Liquid Phases, 170
5.5 Mechanistic Models for Gas Transfer, 170
5.6 The Overall Gas Transfer Rate Coefficient, KL, 179
5.7 Evaluating kL, kG, KL, and a: Effects of Hydrodynamic and Other Operating Conditions, 187
5.8 Summary, 196
6 Gas Transfer: Reactor Design and Analysis 207
6.1 Introduction, 207
6.2 Case I: Gas Transfer in Systems with a Well-Mixed Liquid Phase, 207
6.3 Case II: Gas Transfer in Systems with Spatial Variations in the Concentrations of Both Solution and Gas, 226
6.4 Summary, 241
7 Adsorption Processes: Fundamentals 257
7.1 Introduction, 257
7.2 Examples of Adsorption in Natural and Engineered Aquatic Systems, 262
7.3 Conceptual, Molecular-Scale Models for Adsorption, 266
7.4 Quantifying the Activity of Adsorbed Species and Adsorption Equilibrium Constants, 268
7.5 Quantitative Representations of Adsorption Equilibrium: The Adsorption Isotherm, 269
7.6 Modeling Adsorption Using Surface Pressure to Describe the Activity of Adsorbed Species, 296
7.7 The Polanyi Adsorption Model and the Polanyi Isotherm, 306
7.8 Modeling Other Interactions and Reactions at Surfaces, 314
7.9 Summary, 320
8 Adsorption Processes: Reactor Design and Analysis 327
8.1 Introduction, 327
8.2 Systems with Rapid Attainment of Equilibrium, 328
8.3 Systems with a Slow Approach to Equilibrium, 340
8.4 The Movement of the Mass Transfer Zone Through Fixed Bed Adsorbers, 354
8.5 Chemical Reactions in Fixed Bed Adsorption Systems, 356
8.6 Estimating Long-Term, Full-Scale Performance of Fixed Beds from Short-Term, Bench-Scale Experimental Data, 357
8.7 Competitive Adsorption in Column Operations: The Chromatographic Effect, 359
8.8 Adsorbent Regeneration, 365
8.9 Design Options and Operating Strategies for Fixed Bed Reactors, 366
8.10 Summary, 369
References, 371
Problems, 371
9 Precipitation and Dissolution Processes 379
9.1 Introduction, 379
9.2 Fundamentals of Precipitation Processes, 380
9.3 Precipitation Dynamics: Particle Nucleation and Growth, 384
9.4 Modeling Solution Composition in Precipitation Reactions, 394
9.5 Stoichiometric and Equilibrium Models for Precipitation Reactions, 397
9.6 Solid Dissolution Reactions, 422
9.7 Reactors for Precipitation Reactions, 426
9.8 Summary, 428
10 Redox Processes and Disinfection 435
10.1 Introduction, 435
10.2 Basic Principles and Overview, 435
10.3 Oxidative Processes Involving Common Oxidants, 441
10.4 Advanced Oxidation Processes, 469
10.5 Reductive Processes, 486
10.6 Electrochemical Processes, 488
10.7 Disinfection, 488
10.8 Summary, 502
PART III REMOVAL OF PARTICLES FROM WATER
11 Particle Treatment Processes: Common Elements 519
11.1 Introduction, 519
11.2 Particle Stability, 521
11.3 Chemicals Commonly Used for Destabilization, 532
11.4 Particle Destabilization, 535
11.5 Interactions of Destabilizing Chemicals with Soluble Materials, 542
11.6 Mixing of Chemicals into the Water Stream, 544
11.7 Particle Size Distributions, 546
11.8 Particle Shape, 551
11.9 Particle Density, 552
11.10 Fractal Nature of Flocs, 552
11.11 Summary, 553
12 Flocculation 563
12.1 Introduction, 563
12.2 Changes in Particle Size Distributions by Flocculation, 564
12.3 Flocculation Modeling, 565
12.4 Collision Frequency: Long-Range Force Model, 572
12.5 Collision Efficiency: Short-Range Force Model, 581
12.6 Turbulence and Turbulent Flocculation, 589
12.7 Floc Breakup, 592
12.8 Modeling of Flocculation with Fractal Dimensions, 594
12.9 Summary, 596
13 Gravity Separations 603
13.1 Introduction, 603
13.2 Engineered Systems for Gravity Separations, 605
13.3 Sedimentation of Individual Particles, 607
13.4 Batch Sedimentation: Type I, 612
13.5 Batch Sedimentation: Type II, 618
13.6 Continuous Flow Ideal Settling, 622
13.7 Effects of Nonideal Flow on Sedimentation Reactor Performance, 639
13.8 Thickening, 644
13.9 Flotation, 655
13.10 Summary, 669
14 Granular Media Filtration 677
14.1 Introduction, 677
14.2 ATypical Filter Run, 680
14.3 General Mathematical Description of Particle Removal: Iwasaki’s Model, 683
14.4 Clean Bed Removal, 684
14.5 Predicted Clean Bed Removal in Standard Water and Wastewater Treatment Filters, 694
14.6 Head Loss in a Clean Filter Bed, 698
14.7 Filtration Dynamics: Experimental Findings of Changes with Time, 700
14.8 Models of Filtration Dynamics, 709
14.9 Filter Cleaning, 714
14.10 Summary, 717
PART IV MEMBRANE-BASED WATER AND WASTEWATER TREATMENT
15 Membrane Processes 731
15.1 Introduction, 731
15.2 Overview of Membrane System Operation, 732
15.3 Membranes, Modules, and the Mechanics of Membrane Treatment, 734
15.4 Parameters Used to Describe Membrane Systems, 742
15.5 Overview of Pressure-Driven Membrane Systems, 749
15.6 Quantifying Driving Forces in Membrane Systems, 752
15.7 Quantitative Modeling of Pressure-Driven Membrane Systems, 759
15.8 Modeling Transport of Water and Contaminants From Bulk Solution to the Surface of Pressure-Driven Membranes, 773
15.9 Effects of Crossflow on Permeation and Fouling, 792
15.10 Electrodialysis, 816
15.11 Modeling Dense Membrane Systems Using Irreversible Thermodynamics, 834
15.12 Summary, 838
INDEX 847