Adsorption Refrigeration Technology Theory and Application

Systematically covering the technology of adsorption refrigeration, this book provides readers with a technical understanding of the topic as well as detailed information on the state-of-the-art from leading researchers in the field. Introducing readers to background on the development of adsorption refrigeration, the authors also cover the development of adsorbents, various thermodynamic theories, the design of adsorption systems and adsorption refrigeration cycles. The book guides readers through the research process, covering key aspects such as: the principle of adsorption refrigeration; choosing adsorbents according to different characteristics; thermodynamic equations; methods for the design of heat exchangers for adsorbers; and the advanced adsorption cycles needed. It is also valuable as a reference for professionals working in these areas.

• Covers state-of-the art of adsorption research and technologies for relevant applications, working from adsorption working pairs through to the application of adsorption refrigeration technology for low grade heat recovery
• Assesses sustainable alternatives to traditional refrigeration methods, such as the application of adsorption refrigeration systems for solar energy and waste heat
• Includes a key chapter on the design of adsorption refrigeration systems as a tutorial for readers new to the topic; the calculation models for different components and working processes are also included
• Takes real-world examples giving an insight into existing products and installations and enabling readers to apply the knowledge to their own work

Academics researching low grade energy utilization and refrigeration; Graduate students of refrigeration and low grade energy utilization; Experienced engineers wanting to renew knowledge of adsorption technology,Engineers working at companies developing adsorption chillers; Graduate students working on thermally driven systems; Advanced undergraduates for the Refrigeration Principle as a part of thermal driven refrigeration technology.

About the Authors xiii

Preface xv

Acknowledgments xvii

Nomenclature xix

1 Introduction 1

1.1 Adsorption Phenomena 2

1.2 Fundamental Principle of Adsorption Refrigeration 3

1.3 The History of Adsorption Refrigeration Technology 5

1.4 Current Research on Solid Adsorption Refrigeration 7

1.4.1 Adsorption Working Pairs 7

1.4.2 Heat Transfer Intensification Technology of Adsorption Bed 8

1.4.3 Low Grade Heat Utilization 10

1.4.4 Solar Energy Utilization 11

1.4.5 Advanced Adsorption Refrigeration Cycle 12

1.4.6 Commercialized Adsorption Chillers 14

1.4.7 Current Researches on the Adsorption Theory 15

References 18

2 Adsorption Working Pairs 23

2.1 Adsorbents 23

2.1.1 Physical Adsorbents 23

2.1.2 Chemical Adsorbents 28

2.1.3 Composite Adsorbents 29

2.2 Refrigerants 30

2.2.1 Most Common Refrigerants 30

2.2.2 Other Refrigerants 31

2.3 Adsorption Working Pairs 31

2.3.1 Physical Adsorption 31

2.3.2 Chemical Adsorption Working Pairs 33

2.3.3 The Heat and Mass Transfer Intensification Technology and Composite Adsorbents 35

2.4 Equilibrium Adsorption Models 36

2.4.1 Equilibrium Models for Physical Adsorption 37

2.4.2 Equilibrium Models for Chemical Adsorption 38

2.5 Methods to Measure Adsorption Performances 39

2.6 Comparison of Different Adsorption Refrigeration Pairs 42

References 43

3 Mechanism and Thermodynamic Properties of Physical Adsorption 47

3.1 Adsorption Equations 48

3.1.1 Polanyi Adsorption Potential Theory and Adsorption Equation 48

3.1.2 The Improved Adsorption Equation 52

3.1.3 Simplified D-A Equation and Its Application 56

3.1.4 p-T-x Diagram for Gas-Solid Two Phases Equilibrium 58

3.2 Adsorption and Desorption Heat 60

3.2.1 Thermodynamic Derivation of the Adsorption Heat 61

3.2.2 Simplified Formula of Adsorption and Desorption Heat 62

3.3 Equilibrium Adsorption and Adsorption Rate 63

3.3.1 The Equilibrium Adsorption and Non-equilibrium Adsorption Process 63

3.3.2 Diffusion Process of Adsorbate Inside Adsorbent 65

3.3.3 The Adsorption Rate and the Mass Transfer Coefficient Inside the Adsorbent 66

3.3.4 Typical Model of Adsorption Rate 67

References 68

4 Mechanism and Thermodynamic Properties of Chemical Adsorption 71

4.1 The Complexation Mechanism of Metal Chloride–Ammonia 71

4.2 The Clapeyron Equation of Metal Chloride-Ammonia 72

4.2.1 The General Clapeyron Equations 72

4.2.2 The Principle and Clapeyron Diagram of Metal Chloride-Ammonia Adsorption Refrigeration 74

4.3 Chemical Adsorption Precursor State of Metal Chloride–Ammonia 76

4.3.1 Chemical Adsorbent with Different Expansion Space 78

4.3.2 Attenuation Performance of the Adsorbent and Its Chemical Adsorption Precursor State 80

4.3.3 Isobaric Adsorption Performance and Activated Energy 83

4.4 Reaction Kinetic Models of Metal Chlorides–Ammonia 84

4.4.1 The Model Based on Phenomena and Proposed by Tykodi 85

4.4.2 The Global Reaction Model Proposed by Mazet 85

4.4.3 The Model Based on the Phenomena and Proposed by Goetz 86

4.4.4 Other Simplified Chemisorption Models 89

4.5 Refrigeration Principle and Van’t Hoff Diagram for Metal Hydrides–Hydrogen 91

4.5.1 Adsorption Refrigeration Characteristics and Van’t Hoff Diagram 91

4.5.2 The Novel Adsorption Refrigeration Theory of Metal Hydrides–Hydrogen 93

References 94

5 Adsorption Mechanism and Thermodynamic Characteristics of Composite Adsorbents 97

5.1 The Characteristics of Porous Media 97

5.1.1 Activated Carbon Fiber 98

5.1.2 The Characteristics of Graphite 99

5.1.3 Expanded Natural Graphite (ENG) 100

5.1.4 Expanded Natural Graphite Treated by the Sulfuric Acid (ENG-TSA) 104

5.1.5 Graphite Fiber 108

5.2 The Preparation and Performance of the Composite Adsorbent 109

5.2.1 Composite Absorbents Using the Graphite as the Matrix 109

5.2.2 Composite Adsorbent with ENG-TSA as Matrix 113

5.2.3 Composite Adsorbents with Activated Carbon as Matrix 118

5.2.4 Composite Adsorbent with Activated Carbon Fiber as Matrix 121

5.2.5 Composite Adsorbents with Silica Gel as Matrix 123

5.3 Adsorption Kinetics of Composite Adsorbents 128

5.3.1 Dynamics Characteristics of Composite Adsorbents with the Matrix of Silica Gel 128

5.3.2 Dynamics Characteristics of Composite Adsorbents with the Matrix of Activated Carbon Fiber 129

5.3.3 Dynamics Characteristics of Composite Adsorbents with the Matrix of Activated Carbon 130

References 131

6 Adsorption Refrigeration Cycles 135

6.1 Basic Adsorption Refrigeration Cycles 135

6.1.1 The Basic Intermittent Adsorption Refrigeration Cycle and Its Clapeyron Diagram 135

6.1.2 Continuous Adsorption Refrigeration Cycle 139

6.1.3 Thermodynamic Calculation and Analysis of a Basic Cycle 141

6.2 Heat Recovery Concept Introduced in the Adsorption Refrigeration Cycle 144

6.3 The Heat Recovery Process of Limited Adsorbent Bed Temperature 145

6.3.1 Two-Bed Heat Regeneration Cycle 145

6.3.2 The Examples for the Thermodynamic Calculation of Two-Bed Heat Regenerative Adsorption Refrigeration Cycle 147

6.3.3 Cascading Cycle 149

6.3.4 The System Design of a Cascading Cycle, Working Process Analysis, and the Derivation for the COP of Triple Effect Cycles 153

6.4 Thermal Wave Cycles 156

6.4.1 The Principle of the Basic Thermal Wave Cycle 156

6.4.2 Calculation of the Thermal Wave Cycle 159

6.4.3 Convective Thermal Wave Cycle 168

6.4.4 Mathematical Model of Convective Thermal Wave Cycle 169

6.4.5 Thermal Wave Heat Recovery Cycle for Multi-Bed Systems 176

6.4.6 The Properties of Multi-Bed Thermal Wave Recovery Cycle 176

6.5 The Optimized Cycle Driven by the Mass Change 178

6.5.1 Mass Recovery Cycle 178

6.5.2 Multi-Stage Cycle 183

6.5.3 Resorption Cycle 187

6.6 Multi-Effect and Double-Way Thermochemical Sorption Refrigeration Cycle 192

6.6.1 Solid-Gas Thermochemical Sorption Refrigeration Cycle with Internal Heat Recovery Process 192

6.6.2 Combined Double-Way Thermochemical Sorption Refrigeration Cycle Based on the Adsorption and Resorption Processes 199

6.6.3 Combined Double-Effect and Double-Way Thermochemical Sorption Refrigeration Cycle 203

6.7 Step-by-Step Regeneration Cycle 208

6.7.1 Desiccant Cooling Refrigeration 209

6.7.2 The Ideal Solid Adsorbents for Adsorption Dry Cooling Process 210

6.7.3 The Development of Solid Adsorption Dehumidification Refrigeration 212

6.7.4 The Evaporative Cooling Process of the Dehumidification Refrigeration System 215

6.7.5 Drying Dehumidification Process of Dehumidification Refrigeration Cycle 218

6.8 Adsorption Thermal Storage Cycles 224

6.8.1 Mechanism and Basic Cycle 224

6.8.2 Thermodynamic Analysis 227

References 228

7 Technology of Adsorption Bed and Adsorption Refrigeration System 233

7.1 The Technology of Adsorption Bed 233

7.1.1 The Heat Transfer Intensification Technology of Adsorption Bed Using the Extended Heat Exchange Area 235

7.1.2 The Technology for the Heat Transfer Intensification in the Adsorption Bed 236

7.1.3 The Heat Pipe Technology 239

7.1.4 Other Types of Adsorption Bed with Special Design 239

7.2 The Influence of the Heat Capacity of the Metal Materials and Heat Transfer Medium on the Performance of the System 241

7.2.1 The Metal Heat Capacity Ratio vs. the Performance of the System 241

7.2.2 The Residual Heat Transfer Medium (Heating Fluid) in the Adsorption Bed and the Performance of the System 242

7.2.3 The Influence of the Ratio Between the Metal Heat Capacity and the Fluid Heat Capacity on the COP and SCP 243

7.3 Other Components of the Adsorption System 246

7.3.1 Design of Evaporator, Condenser, and Cooler of Low Pressure System 247

7.3.2 Heat Exchanger for Ammonia 251

7.3.3 The Elements for the Control of the Flow 257

7.4 Operation Control of Adsorption Refrigeration System 261

7.4.1 Brief Introduction on Adsorption Refrigeration System and Its Energy Regulation System 261

7.4.2 Security System 263

7.4.3 Program Control System 264

7.4.4 The Computer Control System 266

References 270

8 Design and Performance of the Adsorption Refrigeration System 273

8.1 Adsorption Chiller Driven by Low-Temperature Heat Source 273

8.1.1 Choice of Adsorbent 274

8.1.2 The Innovation Design of the System and Refrigeration Cycle 274

8.1.3 Design of the System Components 278

8.1.4 System Simulation 283

8.1.5 The Analysis on the Mass Transfer Performance of the Adsorbent Bed 290

8.1.6 Performance Analysis of the System 292

8.2 Silica Gel–Water Adsorption Cooler with Chilled Water Tank 304

8.2.1 Description of the Prototype 304

8.2.2 Working Principle 307

8.2.3 Performance Test 309

8.3 Adsorption Chiller Employing LiCl/Silica Gel–Methanol Working Pair 311

8.3.1 System Description 311

8.3.2 Performance Test 312

8.4 Adsorption Ice Maker Adopted Consolidated Activated Carbon–Methanol Working Pair and Used for a Fishing Boat 316

8.4.1 The Heat Transfer Intensification Technologies for the Adsorbent Bed 316

8.4.2 Design of Activated Carbon–Methanol Adsorption Ice Maker 318

8.4.3 The Mathematic Model for the Activated Carbon–Methanol Adsorption Ice Maker 320

8.4.4 The Adsorption Refrigeration Performances of Activated Carbon–Methanol Adsorption Ice Maker 323

8.5 Heat Pipe Type Composite Adsorption Ice Maker for Fishing Boats 332

8.5.1 System Design of the Adsorption Refrigeration Test Prototype 333

8.5.2 Design of the Adsorbent Bed 336

8.5.3 Simulation Model 337

8.5.4 The Construction of the Adsorption Refrigeration System 344

8.5.5 Studies on the Performances of the Adsorption Refrigeration Prototype 345

8.5.6 Comparison between the Experimental Results and the Simulation Results 356

8.6 Two Stage Adsorption Refrigerator 356

8.6.1 System Design 356

8.6.2 Schematic Diagram of the Two-Stage Sorption Refrigeration Cycle 358

8.6.3 Performance Test 359

8.7 Adsorption Refrigerator Using CaCl2/Expanded Graphite-NH3 362

8.7.1 Structure of Adsorption Refrigerator 362

8.7.2 Performance Test 365

8.8 Adsorption Refrigerator Using CaCl2/Activated Carbon–NH3 368

8.8.1 System Description 368

8.8.2 Performance Test 370

8.9 System Design and Performance of an Adsorption Energy Storage Cycle 373

8.9.1 Thermodynamic Analysis of the Adsorption Energy Storage Cycle 374

8.9.2 Adsorption Air-Conditioning Prototype with the Energy Storage Function 379

8.9.3 Experimental Study on Adsorption Cold Storage Cycle 383

8.9.4 Application of the Adsorption Energy Storage Cycle 389

References 390

9 Adsorption Refrigeration Driven by Solar Energy and Waste Heat 393

9.1 The Characteristics and Classification of Adsorption Refrigeration Systems Driven by Solar Energy 393

9.2 Design and Application of Integrated Solar Adsorption Refrigeration Systems 394

9.2.1 The Performance Index of Integrated Solar Adsorption Refrigeration System 394

9.2.2 The Design and Application of the Activated Carbon–Methanol Adsorption Ice Maker Driven by a Flat-Plate Type Solar Collector 396

9.2.3 The Design Examples of the Activated Carbon–Methanol Ice Maker Driven by Evacuated Tube Collector 408

9.3 The Introduction of the Typical Integrated Solar Adsorption System 416

9.3.1 The Flat-Plate Solar Adsorption Ice Maker 416

9.3.2 The Solar Adsorption Refrigeration System with Transparent Honeycomb Cover 418

9.3.3 The Activated Carbon–Methanol Solar Adsorption Ice Maker with Reflective Plate 419

9.3.4 The Adsorption Refrigeration System with the Working Pair of Activated Carbon–Ammonia 420

9.3.5 Strontium Chloride–Ammonia Adsorption Refrigeration System 421

9.3.6 Silica Gel–Water Solar Adsorption Ice Maker 422

9.4 Design and Examples of Separated Solar Adsorption Refrigeration Systems 423

9.4.1 Design and Application Example of the Solar Air Conditioner for Green Building 424

9.4.2 Design and Application Example of the Solar Adsorption Chiller in Grain Storage System 431

9.4.3 Examples for the Application of Separated Solar Powered Adsorption Refrigeration Systems 434

9.5 Solar Powered Adsorption Refrigeration by Parabolic Trough Collector 436

9.5.1 The Research Work Done by Fadar 436

9.5.2 Introduction on the System Constructed by Shanghai Jiao Tong University 437

9.5.3 Experimental Results for the System Constructed by Shanghai Jiao Tong University 441

9.6 Other Types of Solar Adsorption Refrigeration Systems 443

9.6.1 Solar Cooling Tube 443

9.6.2 Solar Air Conditioner with Heat Storage Function 444

9.7 Adsorption Refrigeration Technology for the Utilization of Waste Heat 446

9.7.1 The Usage of Waste Heat from the Engine 446

9.7.2 Waste Heat Recovery Methods 447

9.7.3 The Advantages of Adsorption Refrigeration Technology for the Waste Heat Recovery 449

9.8 Application of Adsorption Refrigeration Systems Driven by Waste Heat 449

9.8.1 The Application of Zeolite–Water Adsorption System as Locomotive Air Conditioner 449

9.8.2 The Application of the Silica Gel–Water Adsorption Chiller in CCHP System 464

9.8.3 Other Examples of the Adsorption Refrigeration Systems for Waste Heat Utilization 482

References 485

Index 489

Ruzhu Wang, Liwei Wang, Jingyi Wu,Shanghai Jiao Tong University, China