Understanding Membrane Distillation and Osmotic Distillation

This book addresses principles and practical applications of membrane distillation and osmotic distillation, separation technologies which are gaining increasing attention due to their advantages over conventional concentration processes. Addresses membrane and osmotic distillation, two closely related and novel processes that offer several advantages over conventional concentration processes Has a widespread impact and application of the technology in industries such as food, environment, and nuclear clean-up / containment Covers theoretical aspects of both processes, the properties of hydrophobic membranes, process economics, integrated processes and future prospects. Caters the presentation caters for the diversity of readership with respect to links with membrane technologies.

Autorentext

ROBERT A. JOHNSON, BSC, MSC, PHD (UQ) is a lecturer in Physical Chemistry
and Chemical Technology at Queensland University of Technology. Prior to entering academia he was a Research Director at Syrinx Research Institute where he oversaw the development of Osmotic Distillation from a laboratory novelty to the pilot plant stage.

MINH H. NGUYEN, BE, GRAD DIP, MSC (UNSW), PHD (UTS) is a Conjoint Associate Professor at the University of Newcastle and an Adjunct Associate Professor at Western Sydney University. He has a lifetime of experience in scientific research and development in industry, research laboratories and university. He was among the pioneers in research and development in membrane technology, in particular membrane distillation and osmotic distillation.

Klappentext

Laboratory chemists use distillation to separate small quantities of individual compounds from each other while industrial operators use this process to effect large-scale separations involving complex materials such as liquid foods, beverages, seawater, petroleum products and factory waste streams. Membrane distillation and osmotic distillation are novel, closely related processes that offer several advantages over conventional distillation processes.

This book addresses the principles and applications of membrane distillation and osmotic distillation, separation technologies that are gaining increasing attention for a wide range of industrial applications. Written by leading practitioners of these critical distillation methods, Understanding Membrane Distillation and Osmotic Distillation serves as a key resource for readers involved in chemical engineering, food processing, desalination, wastewater treatment or pollution control. Key benefits of this book include: Discussion of wide-ranging applications in the food, brewing, pharmaceuticals, desalination, wastewater treatment and pollution control industries. Consideration of theoretical and practical aspects, economics and the potential for integrated membrane processes to provide solutions to many separation problems. A complete package for researchers and plant operators.

Inhalt
Preface xi

Acknowledgments xiii

About the Authors xv

Nomenclature xvii

1 General Introduction 1

1.1 Overview of Distillation Processes 1

1.2 Membrane Distillation (MD) 5

1.2.1 Historical Perspective 5

1.2.2 MD Process 7

1.3 Osmotic Distillation (OD) 11

1.3.1 Historical Perspective 11

1.3.2 OD Process 12

1.4 MD and OD as Alternatives to Established Stripping Processes 14

1.4.1 Nonvolatile Solutes Retention 15

1.4.2 Minimization of Heat Damage to Feed Components 15

1.4.3 Organic Volatiles Retention 18

1.4.4 Production of Highly Concentrated Solutions 19

1.4.5 Utilization of Waste Heat or Heat from Natural Sources 20

1.5 Established Stripping Processes 20

1.5.1 Multistage Flash Distillation (MSF) 20

1.5.2 Multiple-Effect Distillation (MED) 22

1.5.3 Vapor Compression Distillation (VCD) 25

1.5.4 Freeze Concentration (FC) 26

1.5.5 Reverse Osmosis (RO) 28

1.5.6 Electrodialysis (ED) 31

1.6 Other Membrane Processes 32

1.6.1 Microfiltration (MF) 33

1.6.2 Ultrafiltration (UF) 34

1.6.3 Nanofiltration (NF) 36

1.7 Concluding Remarks 38

2 Theoretical Aspects of Membrane Distillation 39

2.1 Introduction 39

2.2 MD Theory 40

2.2.1 Preliminary Considerations 40

2.2.2 Overall Approach to Theoretical Treatment 45

2.2.3 Overall Driving Force, pb 46

2.2.4 Overall Mass Transfer Coefficient, K 50

2.2.5 Vapor Pressure Polarization Coefficient, ;;v 60

2.3 MD Membrane Requirements 68

2.4 Effect of Operating Conditions on MD Performance 71

2.4.1 Feed Temperature 71

2.4.2 Strip Temperature 72

2.4.3 Feed Solutes Concentration 72

2.4.4 Feed Velocity 73

2.4.5 Strip Velocity 75

2.4.6 Membrane Type 76

2.4.7 Summary of Conditions Affecting MD Performance 77

2.5 MD Process Economics 79

2.6 Concluding Remarks 82

3 Theoretical Aspects of Osmotic Distillation 85

3.1 Introduction 85

3.2 OD Theory 87

3.2.1 Preliminary Considerations 87

3.2.2 Overall Approach to Theoretical Treatment 90

3.2.3 Overall Driving Force, pb 92

3.2.4 Overall Mass Transfer Coefficient, K 96

3.2.5 Vapor Pressure Polarization Coefficient, ;;v 97

3.3 OD Membrane Requirements 97

3.4 Effect of Operating Conditions on OD Performance 98

3.4.1 Osmotic Agent Concentration 99

3.4.2 Feed Solutes Concentration 99

3.4.3 Feed Velocity 100

3.4.4 Strip Velocity 100

3.4.5 Feed and Strip Temperature 101

3.4.6 Membrane Type 101

3.4.7 Summary of Conditions Affecting OD Performance 103

3.5 OD Process Economics 103

3.6 Concluding Remarks 105

4 Properties of Macroporous Hydrophobic Membranes 107

4.1 Introduction 107

4.2 Theoretical Aspects of Membrane Hydrophobicity 108

4.3 Membrane Types 111

4.3.1 Polypropylene (PP) 113

4.3.2 Polytetrafluoroethylene (PTFE) 115

4.3.3 Polyvinylidene Fluoride (PVDF) 118

4.3.4 Tailored PVDF-Based Membranes 118

4.3.5 Polyazole Membranes 119

4.3.6 Nanofibrous PVDFPTFE Membranes 121

4.3.7 Surface-Modified Hydrophilic Membranes 122

4.3.8 Inorganic Membranes 122

4.4 Fouling of Hydrophobic Membranes 123

4.4.1 Inorganic Fouling or Scaling 126

4.4.2 Organic Fouling 127

4.4.3 Biological Fouling 129

4.4.4 Clean-in-Place (CIP) Operating Conditions 129

4.5 Protection Against Membrane Wet-Out 130

4.6 Hydrophobicity Restoration 132

4.7 Membrane Module Requirements 132

4.7.1 Plate-and-Frame Modules 133 4.7.2 Spiral Wound Modules 134&...