Front Cover

Thermal Solar Desalination

Copyright Page

Contents

Author Biographies

Preface

Introduction

1. Desalination Methods and Technologies—Water and Energy

1.1 Introduction

1.2 What Is Desalination?—Where Does It Apply?

1.2.1 The Desalination Processes

1.2.1.1 Distillation Processes

1.2.1.2 Reverse Osmosis

1.2.1.3 Electrodialysis and Electrodialysis Reversal

1.2.1.4 Mechanical Vapor Compression

1.2.1.5 Crystallization Processes

1.2.1.6 Ion Exchange Processes

1.3 Operation Steps of a Desalination Plant

1.4 Water and Energy

1.4.1 Energy Necessary for Desalination

1.5 Thermal Solar Desalination

1.6 New Trends in Desalination

1.6.1 Hybridization

1.6.2 Forward Osmosis

References

General Interest Books

General Interest Journals and Websites

2. Water, the Raw Material for Desalination

2.1 Introduction

2.1.1 What is Really Water?

2.1.1.1 The Molecular Structure of Water

2.1.2 Natural Waters

2.1.3 Water Resources

2.1.4 The Water Problem

2.1.5 Water Demand

2.1.6 Recycling and Reuse of Water

2.2 Water and Seawater Properties—Definitions

2.2.1 General Definitions

2.2.2 Basic Chemical Relations

2.3 The Chemical Composition of Seawater

2.3.1 The Chemistry of Seawater

2.3.2 What Is Salinity(S)—Chlorinity (Cl)

2.3.3 Hardness—Alkalinity

2.4 Properties of Seawater

2.4.1 General

2.4.1.1 The Gibbs Function—Equation of State

2.4.1.2 Seawater as an Electrolyte Solution

2.4.1.3 pH

2.4.1.4 Density (ρ)

2.4.1.5 Activity (α) and Activity Coefficients (γ)—Chemical Potential (μ)

2.4.1.6 Thermal Conductivity (λ, k)

2.4.1.7 Diffusion—Diffusion Coefficient (D)

2.4.1.8 Viscosity (η, ν)

2.4.1.9 Ionic Strength (I)

2.4.1.10 Enthalpy (H)—Specific Enthalpy (h)

2.4.1.11 Enthalpy of Evaporation (hev, or hfg)

2.4.1.12 Vapor Pressure p–Boiling Point Elevation (ΔTel or Δtel)

2.4.1.13 Heat Capacity(C)—Specific Heat (cp, cv)

2.4.1.14 Freezing Point of Water and Seawater

2.4.1.15 The p-V-T Diagram of Water

2.4.1.16 Electrical Conductance (EC)/Electrical Resistance (RC)

2.4.1.17 Dissolved Gases and the Carbonate System

2.4.1.18 Osmosis—Osmotic Coefficient

2.5 Suspended Particulate Material in Seawater

2.5.1 Suspended Matter Evaluation

2.6 Quality of Drinking and Utilization Water

2.7 Corrosion and Scale Formation

2.7.1 Corrosion

2.7.2 Scale Formation and Fouling

2.7.2.1 Alkaline Scale Formation

2.7.2.2 Sulfate Scale, or Acid Scale

2.7.3 Scale Prevention

2.7.3.1 Acid Injection

2.7.3.2 Injection of Carbon Dioxide

2.7.3.3 Polyphosphates as Scale Inhibitors

2.7.3.4 The Seeding Technique

2.8 Conclusion

References

3. Solar Distillation—Solar Stills

3.1 Introduction

3.1.1 Definitions

3.1.1.1 Absorptivity–Transmittance–Reflectance of Cover Material

3.1.1.2 Solar Radiation

3.1.1.3 Solar Stills

3.1.1.4 Surface Conditions Inside the Still

3.2 Solar Stills

3.2.1 Manufacture–Maintenance

3.2.2 Materials of Construction

3.2.2.1 Basin Materials

3.2.2.2 The Absorbing Black Material

3.2.2.3 The Frames

3.2.2.4 Glazing Material

3.2.2.5 Insulation Material

3.2.2.6 The Sealing Material

3.2.2.7 Auxiliary Components

3.2.3 Rain Catchment Canals

3.2.4 Conditions for Proper Installation/Operation of Solar Stills

3.3 Operation Principles of Solar Distillation—Solar Stills

3.3.1 The Phase Movement Inside the Still

3.3.2 The Cover Inclination

3.3.3 The Optical Behavior of the Transparent Cover

3.3.4 Thermal Behavior of Solar Stills

3.3.4.1 Heat Balance—Heat Transfer—Heat Transfer Coefficients

Heat Balance

Heat Transfer Rate Inside the Still

Overall Heat Transfer Coefficients

3.3.4.2 Efficiency, Output, and Performance of Solar Stills

3.3.5 Diurnal and Nocturnal Operation—the Impact of Water Depth

3.3.5.1 Diurnal Operation of a Simple Solar Still

3.3.5.2 Nocturnal Operation

3.3.6 The Significance of the Water Depth

3.3.7 Increasing Productivity of Simple Solar Stills

3.3.7.1 Increasing Vapor Condensation Rate

3.3.7.2 Increasing Solar Radiation Absorption

3.3.7.3 Increasing Feed Seawater Temperature

3.3.7.4 Connected to Flat Plate Collectors and to Storage

3.4 Various Types of Solar Stills

3.4.1 Wick and Multiwick Solar Stills

3.4.2 Multiple Effect Solar Stills

3.4.3 Incline Solar Stills

3.4.4 Tubular Solar Stills

3.4.5 Vertical Solar Stills

3.4.6 Other Types of Solar Stills—Solar Plants

3.5 Economic Evaluation of Solar Distillation

3.6 Conclusion

References

Extended Recent Reviews on Solar Stills

4. Membrane Distillation

4.1 Introduction

4.1.1 A Short Historical Introduction

4.2 Terminology

4.3 Membrane Distillation

4.3.1 The Process

4.3.2 Process Configurations

4.3.3 Advantages, Disadvantages, and Applications

4.4 Mass and Heat Transfer

4.4.1 Direct Contact Membrane Distillation

4.4.1.1 Mass Transfer

4.4.1.1.1 Mass Transfer Through the Feed Boundary Layer

4.4.1.1.2 Mass Transfer Through the Membrane

4.4.1.2 Heat Transfer

4.4.1.2.1 Heat Transfer Through the Thermal Boundary Layer

4.4.1.2.2 Heat Transfer Through the Membrane

4.4.2 Air Gap Membrane Distillation

4.4.2.1 Mass Transfer

4.4.2.2 Heat Transfer

4.4.3 Sweep Gas Membrane Distillation

4.4.4 Vacuum Membrane Distillation (VMD)

4.4.5 Performance Parameters of MD Process

4.5 Characteristics of MD Configurations

4.6 Heat Recovery

4.7 Solar Powered Membrane Distillation

4.7.1 Technoeconomic Performance of Solar-Powered Systems

4.8 Membrane’s Characteristic Properties

4.8.1 Membrane Permeability

4.8.2 Liquid Entry Pressure (LEP)

4.9 Membrane Modules

4.10 Membrane Types

4.10.1 Commercial Membranes

4.10.2 Membrane Synthesis

4.10.2.1 Polymeric Membranes (Polymer Blends and Additives)

4.10.2.2 Composite Membranes (Multilayer, Hydrophilic/Hydrophobic)

4.10.2.3 Ceramic Membranes

4.10.2.4 Carbon Nanotubes

4.10.2.5 Electrospun Membranes

References

5. Humidification–Dehumidification

5.1 Introduction

5.2 Definitions

5.3 General Operation Principles

5.3.1 The Setup of Single Effect Conventional H/D System

5.3.2 Basic Operation Principles

5.3.3 Humidifying Step—h–x Diagram

5.4 Mathematical Models

5.4.1 Conventional Single Effect H/D Process

5.4.1.1 For the Humidifier Tower

5.4.1.2 For the Dehumidifier

5.4.2 The Dewvaporation Process

5.5 Multiple Effect Humidification–Dehumidification (MEH)

5.5.1 H/D System Using Two Collector Fields

5.6 Other Concepts of the H/D Method

5.6.1 The Desiccant Absorption/Desorption H/D Process

5.6.2 Membrane Drying Humidification

5.6.3 H/D Under Varied Humidification Cycle

5.6.4 H/D Systems with Vapor Compression

5.7 Solar H/D Systems with Storage Tanks

5.8 The Economics of the H/D Method

5.9 Coupling Solar Stills or H/D Systems to Greenhouses

References

6. Indirect Solar Desalination (MSF, MED, MVC, TVC)

6.1 Introduction

6.1.1 The Available Solar Energy

6.1.2 Solar Collectors

6.1.2.1 Solar Ponds

6.1.2.2 Flat-Plate Collectors

6.1.2.3 Evacuated Tube Collectors

6.1.2.4 Concentrating Solar Collectors

6.2 Short Historical Review

6.3 Definitions and Nomenclature

6.4 Factors Influencing the Selection of the Desalination System

6.4.1 Energy Demand

6.4.2 Water Demand

6.5 Factors Influencing the Selection of the Solar System

6.5.1 Suitability of Solar Collectors for Desalination

6.6 Conventional Desalination Systems—Distillation Methods

6.6.1 Multiple Effect Distillation

6.6.1.1 The Temperature Distribution

6.6.1.2 Brief Mathematical Analysis

6.6.1.3 Low-Temperature MED Systems

6.6.2 Multistage Flash

6.6.2.1 Thermal Analysis of an MSF Distillation System

6.6.3 Mass and Energy Balance

6.6.3.1 Heat and Mass Balance at the Water Cooling Section

6.6.3.2 Heat Transfer Coefficients

6.6.3.3 Temperature Ranges

6.6.4 Distillation with Vapor (Re)Compression (MVC–TVC)

6.6.4.1 Mechanical Vapor Compression

MVC Mathematical Analysis

6.6.4.2 Thermal Vapor Compression

6.7 Dual-Purpose Plants

6.8 Solar Desalination Combinations

References

Appendix A

A.1 General

A.2 General Units and Symbols Based in SI

References

Abbreviations

Appendix B

B.1 Seawater Constituents

B.2 Properties of Pure and Natural Waters

B.3 Properties of Saturated Vapor in Air

B.4 Electrical Properties of Constituents in Seawater

B.5 Solubility of Gases in Seawater

B.6 Various Characteristics

Appendix C

C.1 Diagrams of Seawater Properties

Index

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