With a growing population, climate change and greater water demand, desalination has increasingly become a part of the solution to regional water scarcity - seawater desalination capacity has roughly doubled in the past ten years. Desalination has also begun to receive more attention in academia, with research focusing on improving energy efficiency and system robustness and lowering capital costs.
With this book, an introduction is given to the basics and fundamentals of desalination systems. Both, thermal and membrane desalination systems, are covered and discussed in view of energy, exergy, economic and environmental aspects. In the beginning, Introduction to Desalination: Systems, Processes and Environmental Impacts describes multi effect evaporation, vapor compression and multi-stage flashing. Further chapters deal with common membrane-based separations like reverse osmosis and membrane filtration, forward osmosis, diffusion dialysis and pervaporation as well as thermo-osmosis, electrodialysis and electrodeionization. Subsequently, hybrid systems are discussed, and the economic analysis of such systems and their environmental impact are highlighted. Each chapter contains theoretical and practical examples and concludes with questions and problems for self-study.
Needed: Desalination has become a part of the solution to regional water scarcity and an introductory book in this field is urgently needed.
Balanced Approach: Presents the fundamentals of thermal and membrane desalination systems.
Learning Material: Each chapter includes exercises for self-study and Instructors can find teaching material online.
Introduction to Desalination: Systems, Processes and Environmental Impacts is an important resource for master's students in engineering sciences, lecturers in chemical and mechanical engineering, engineers, environmental chemists, as well as process engineers, engineering scientists in industry, and environmental consultants.
Table of Contents
Preface xiii
1 Introduction 1
1.1 What is Desalination? 1
1.2 Aims of Desalination Processes 2
1.3 Desalination Processes 3
1.4 Desalination Technologies 6
1.4.1 Thermal Desalination System 6
1.4.2 Membrane Desalination System 10
1.5 Which Desalination System is the Best? 12
1.6 Thermo-Physical Properties of Water 13
1.6.1 Potable Water 13
1.6.2 Seawater 13
References 22
A. Review Questions 23
Part I Thermal Desalination Systems 27
2 Multi-effect Evaporator (MEE) 29
2.1 Introduction 29
2.2 Vaporization 29
2.3 MEE Processes 31
2.4 MEE Configurations 33
2.5 Mathematical Modeling Algorithm for Thermal Systems 34
2.6 MEE Mathematical Model 38
2.6.1 Forward Flow Mathematical Modeling MEE-FF 39
2.6.1.1 Energy Analysis 39
2.6.1.2 Exergy Analysis 45
2.6.2 Backward Flow Mathematical Model MEE-BF 53
2.6.3 Parallel Flow Mathematical Model MEE-PF-Cross Type 60
2.7 MEE Integrated Auxiliary Devices 61
2.8 Characteristics of MEE Desalination Systems 63
2.9 MEE Energy Consumption and Cost 66
References 66
A. Review Questions 67
B. Problems 69
C. Essay, Design, and Open-Ended Problems 73
3 Multi-stage Flashing (MSF) 77
3.1 Flashing Stage 80
3.2 MSF Once-Through Configuration MSF-OT 81
3.2.1 MSF-OT Once-Through Model 82
3.2.1.1 Optimum Number of MSF Stages 88
3.3 MSF-Brine Recirculation (MSF-BR) 88
3.3.1 Detailed Mathematical Model of MSF-BR System 89
3.4 MSF with Brine Mixer (MSF-BM) 102
3.5 Material of Construction 103
References 103
A. Review Questions 103
B. Problems 105
C. Essay, Design and Open-Ended Problems 110
4 Vapor Compression: Thermal Vapor Compression (TVC), Mechanical Vapor Compression (MVC), andMechanical Vapor Recompression (MVR) 113
4.1 Thermal Vapor Compression (TVC) 114
4.2 TVC Mathematical Modeling 116
4.3 Mechanical Vapor Compression (MVC) 127
4.4 SEE-MVC Mathematical Modeling 128
4.5 Mechanical Vapor Recompression (MVR) 133
4.6 Characteristics of VC Desalination System 135
References 136
A. Review Questions 137
B. Problems 138
C. Essay, Design and Open-Ended Problem 141
Part II Membrane Desalination Systems 145
5 Pressure Gradient Driving Force: Reverse Osmosis (RO), Nanofiltration (NF), Ultrafiltration (UF), Microfiltration (MF) 147
5.1 Semipermeable Membrane: Properties and Modules 147
5.2 Membrane Modules (Configurations) 150
5.3 Natural Osmosis Phenomenon 152
5.4 Reverse Osmosis (RO) 155
5.5 Membrane Performance 157
5.5.1 Recovery Ratio (RR) 157
5.5.2 Net Driving Pressure (NDP) 158
5.5.3 Solute Rejection Rate (RjR) 158
5.5.4 Volume Recovery (VR) 158
5.5.5 Permeate Flux (J) 158
5.5.6 Specific Energy Consumption (SEC) 158
5.5.7 Concentration Polarization Factor (𝛽) 158
5.5.8 Rate of Solvent Pass 159
5.5.9 Rate of Solute Pass 159
5.5.10 Concentration Factor (CF) 159
5.6 RO System Components 162
5.7 RO Advantages and Disadvantages 163
5.8 RO Performance Using Software 164
5.9 RO Mathematical Model 175
5.10 Energy Recovery Device (ERD) 177
5.10.1 Pressure Exchanger (PX) 178
5.11 MF, UF, and NF Membranes: Materials and Applications 187
5.11.1 MF and UF 187
5.11.2 Nanofiltration (NF) 187
References 193
A. Review Questions 193
B. Problems 197
C. Essay, Design and Open-Ended Problems 201
6 Electrical Potential Driving Force: Electrodialysis (ED), Electrodialysis Reversed (EDR) 205
6.1 Electrodialysis 205
6.2 Electrodialysis Principle 208
6.3 Conservation of Ionic Mass 210
6.4 ED Mathematical Modeling 210
6.5 ED Characteristics 212
6.5.1 Limiting Current Density (LCD) 213
6.5.2 Substance Removal Rate (G) 213
6.5.3 Normality (N) 214
6.5.4 Current Intensity (I) 214
6.6 Advantages and Disadvantages of ED 217
6.7 Electrodialysis Reversed (EDR) 218
References 218
A. Review Questions 219
B. Problems 220
C. Essay, Design and Open-Ended Problems 222
7 Temperature Gradient Driving Force: Membrane Distillation (MD) 225
7.1 MD Processes and Configurations 227
7.2 MD Advantages and Disadvantages 229
7.3 Characteristics of Hydrophobic Membranes 230
7.3.1 Liquid Entry Pressure (LEP) 231
7.3.2 Trans-membrane Flux (N) 234
7.3.3 Membrane Thermal Conductivity (Km) 234
7.4 Heat and Mass Transfer Models for DCMD 235
7.4.1 DCMD Heat Transfer Mathematical Model 235
7.4.2 MD Mass Transfer Model 237
7.4.2.1 Fouling and Scaling in MD 241
References 242
A. Review Questions 243
B. Problems 245
C. Essay, Design and Open-Ended Problems 245
8 Concentration Gradient Driving Force: Natural Osmosis, Forward Osmosis (FO), Pervaporation (PV), Dialysis 251
8.1 Forward Osmosis (FO) 252
8.1.1 FO Advantages and Disadvantages 255
8.1.2 FO Solvent and Solute Fluxes 257
8.1.3 FO Mass Transfer 259
8.1.4 FO Configuration 260
8.1.5 FO Concentration Polarization (CP) 264
8.2 Pervaporation (PV) 267
8.2.1 Pervaporation Mathematical Modeling and Performance Parameters 269
8.3 Dialysis 274
8.3.1 Neutralization Dialysis (ND) 276
8.4 Summary: Membrane Desalination Systems 277
References 279
A. Review Questions 280
B. Problems 283
C. Essay, Design, and Open-Ended Problems 285
Part III Nonconventional Desalination Systems 289
9 Renewable Energy and Desalination: Solar, Wind, Geothermal 291
9.1 Solar Energy 294
9.1.1 Direct Solar Desalination Systems 295
9.1.1.1 Solar Pond 295
9.1.1.2 Solar Still 297
9.1.1.3 Internal Heat Transfer 298
9.1.1.4 External Heat Transfer 299
9.1.2 Indirect Solar Collectors 303
9.1.2.1 Thermal Solar Collectors (TSC) 303
9.1.2.2 Solar Photovoltaic (PV) 307
9.2 Calculation of Solar Radiation on Inclined Surface 307
9.3 Wind Energy 310
9.3.1 Wind Turbine Configurations 311
9.3.2 Wind Turbine Mathematical Model 311
9.3.3 Advantages and Disadvantages of Wind Turbine 322
9.4 Geothermal Energy 326
9.5 Geothermal Well Performance 329
9.5.1 Geothermal Energy and Desalination 330
9.6 Advantages of Geothermal Energy 332
References 335
Questions and Problems 337
10 Hybrid Desalination System 349
10.1 Case I: Cogeneration-MSF-RO Hybrid Desalination Systems 350
10.2 Case II: Hybrid SEF-Geothermal Desalination System 355
10.3 Case III: Hybrid MEE-Solar Desalination System 362
10.3.1 MEE-FF System 364
10.3.2 Solar Flat-Plate Collector 364
10.3.3 Mathematical Modeling for Solar Flat-Plate Collector 365
10.4 Case IV: Hybrid MD-RO Desalination System 368
10.4.1 Modeling and Simulation 368
10.4.2 Results and Discussion 370
10.5 Case V: Hybrid Humidification-Dehumidification Desalination System 373
References 377
Essay, Design, and Open-Ended Problems 378
Appendix A Thermo-Physical Properties of Seawater 381
Index 383
