Biomass as a Sustainable Energy Source for the Future
Fundamentals of Conversion Processes

PREFACE xiii

ACKNOWLEDGMENTS xv

LIST OF CONTRIBUTORS xvii

PART I SOCIAL CONTEXT AND STRUCTURAL BASIS OF BIOMASS AS A RENEWABLE ENERGY SOURCES 1

1 Introduction: Socioeconomic Aspects of Biomass Conversion 3
Wiebren de Jong and J. Ruud van Ommen

1.1 Energy Supply: Economic and Environmental Considerations 4

1.2 Ways to Mitigate Threats to a Sustainable Energy Supply 16

1.3 What is Sustainable Supply of Biomass? 20

1.4 Resources and Sustainable Potential of Biomass 25

1.5 A Brief Introduction to Multiproduct Biomass Conversion Techniques 29

Chapter Summary and Study Guide 30

Key Concepts 30

Short-Answer Questions 30

Problems 32

Projects 32

Internet References 33

References 33

2 Biomass Composition, Properties, and Characterization 36
Wiebren de Jong

2.1 Physicochemical Properties 37

2.2 Main Structural Organic Constituents 42

2.3 Minor Organic Constituents 45

2.4 Inorganic Compounds 49

2.5 Proximate and Ultimate Analysis 52

2.6 Heating Values 57

2.7 Ash Characterization Techniques 59

Chapter Summary and Study Guide 61

Key Concepts 62

Short-Answer Questions 62

Problems 63

Projects 65

Internet References 65

References 65

PART II CHEMICAL ENGINEERING PRINCIPLES OF BIOMASS PROCESSING 69

3 Conservation: Mass, Momentum, and Energy Balances 71
Wiebren de Jong

3.1 General Conservation Equation 73

3.2 Conservation of Mass 74

3.3 Conservation of Energy 80

3.4 Conservation of Momentum 90

Chapter Summary and Study Guide 92

Key Concepts 92

Short-Answer Questions 93

Problems 93

Projects 95

Internet Reference 96

References 96

4 Transfer: Basics of Mass and Heat Transfer 97
Dirk J.E.M. Roekaerts

4.1 Introduction 100

4.2 Transport Terms in the Governing Equations 100

4.3 Radiative Heat Transfer 103

4.4 Convective Heat and Mass Transfer 108

4.5 Transfer of Heat and Mass with Phase Change 110

Chapter Summary and Study Guide 124

Key Concepts 124

Short-Answer Questions 125

Problems 125

Projects 127

References 128

5 Reactions: Thermodynamic Aspects, Kinetics, and Catalysis 129
Martina Fantini, Wiebren de Jong, and J. Ruud van Ommen

5.1 Reaction Kinetics 130

5.2 Chemical Equilibrium 138

5.3 Catalysis 148

Chapter Summary and Study Guide 154

Key Concepts 155

Short-Answer Questions 155

Problems 155

Projects 156

References 158

6 Reactors: Idealized Chemical Reactors 159
Lilian de Martín and J. Ruud van Ommen

6.1 Preliminary Concepts 160

6.2 Batch Reactors (BRs) 163

6.3 Steady-State Continuous Stirred Tank Reactors (CSTRs) 167

6.4 Steady-State Plug Flow Reactors (PFRs) 168

6.5 Residence Time and Space Time for Flow Reactors 173

6.6 Deviations from Plug Flow and Perfect Mixing 176

Chapter Summary and Study Guide 180

Key Concepts 181

Short-Answer Questions 181

Problems 181

Project 182

References 183

7 Processes: Basics of Process Design 184
Johan Grievink, Pieter L.J. Swinkels, and J. Ruud van Ommen

7.1 Scope 186

7.2 Characterization of Biomass Processing 187

7.3 Analyzing the Outside of a Process 189

7.4 Analyzing the Inside of a Process 192

7.5 A Design Procedure for Biomass Conversion Processes 195

7.6 Interface with Supply Chain: Input–Output Diagram 201

7.7 Division in Subprocesses 206

7.8 Process Design: Functional Block Diagram 207

7.9 Example of Analysis and Evaluation in Process Design 212

7.10 Integrating Process Units into the Functional Network 222

7.11 Application Potential 224

Chapter Summary and Study Guide 224

Key Concepts 225

Short-Answer Questions 225

Problems 226

Projects 229

Internet References 229

References 229

PART III BIOMASS CONVERSION TECHNOLOGIES 231

8 Physical Pretreatment of Biomass 233
Wiebren de Jong

8.1 Introduction 235

8.2 Harvesting and Transport 236

8.3 Storage 241

8.4 Washing 242

8.5 Size Reduction 243

8.6 Particle Size Characterization 247

8.7 Screening and Classification 249

8.8 Methods of Moisture Reduction 249

8.9 Compaction Technologies 257

8.10 Sequencing the Pretreatment Steps 261

Chapter Summary and Study Guide 261

Key Concepts 261

Short-Answer Questions 262

Problems 263

Projects 264

Internet References 265

References 265

9 Thermochemical Conversion: Direct Combustion 268
Rob J.M. Bastiaans and Jeroen A. van Oijen

9.1 Introduction 270

9.2 Fundamental Conversion Processes 271

9.3 Particle Conversion Modes 273

9.4 Combustion Systems 283

9.5 Emissions 288

Chapter Summary and Study Guide 294

Key Concepts 295

Short-Answer Questions 295

Problems 295

Projects 296

Internet References 296

References 297

10 Thermochemical Conversion: (Co)gasification and Hydrothermal Gasification 298
Sascha R.A. Kersten and Wiebren de Jong

10.1 What is Gasification? A Chemical and Engineering Background 300

10.2 A Short History of Gasification 317

10.3 (Co)gasification Technologies for Dry Biomass 318

10.4 Gasification in an Aqueous Environment: Hydrothermal Biomass Conversion 329

10.5 Gas Cleaning for Biomass Gasification Processes 337

Chapter Summary and Study Guide 348

Key Concepts 348

Short-Answer Questions 349

Problems 350

Projects 353

Internet References 353

References 353

11 Thermochemical Conversion: An Introduction to Fast Pyrolysis 359
Stijn R.G. Oudenhoven and Sascha R.A. Kersten

11.1 Introduction 361

11.2 A First Look at a Liquefaction Process 362

11.3 A First Look at Fast Pyrolysis Oil 363

11.4 Chemistry and Kinetics of Pyrolysis 364

11.5 Processes at the Particle Level 368

11.6 A Closer Look at Pyrolysis Oil 371

11.7 Fast Pyrolysis Processes 374

11.8 Catalytic Pyrolysis 377

11.9 Oil Applications 378

11.10 Outlook 380

Appendix 11.1 Single-Particle Model (Based on the Model by Di Blasi, 1997) 380

Chapter Summary and Study Guide 383

Key Concepts 383

Short-Answer Questions 383

Problems 384

Projects 384

Internet References 385

References 385

12 Thermochemical Conversion: Torrefaction 388
Jaap H.A. Kiel, Arno H.H. Janssen, and Yash Joshi

12.1 Introduction 388

12.2 Fundamentals of Torrefaction 389

12.3 Advantages of Torrefaction 392

12.4 Torrefaction Technology 392

12.5 Torrefaction: An Enabling Technology 397

12.6 The Future of Torrefaction 398

Chapter Summary and Study Guide 399

Key Concepts 399

Short-Answer Questions 399

Problems 400

Projects 401

References 401

13 Biochemical Conversion: Biofuels by Industrial Fermentation 403
Maria C. Cuellar and Adrie J.J. Straathof

13.1 Introduction 404

13.2 First-Generation Bioethanol Processes 406

13.3 Second-Generation Bioethanol Processes 417

13.4 Butanol 428

13.5 Diesel-like Products 429

13.6 Stoichiometric and Thermodynamic Comparison of Fermentative Biofuels 432

13.7 Outlook 436

Chapter Summary and Study Guide 437

Key Concepts 438

Short-Answer Questions 438

Problems 438

Projects 439

References 439

14 Biochemical Conversion: Anaerobic Digestion 441
Robbert Kleerebezem

14.1 Introduction 442

14.2 Biochemical Fundamentals 443

14.3 Thermodynamic Fundamentals 453

14.4 Process Engineering 454

14.5 Outlook and Discussion 463

Chapter Summary and Study Guide 466

Key Concepts 466

Short-Answer Questions 466

Problems 467

Project 467

References 468

15 Biorefineries: Integration of Different Technologies 469
Wiebren de Jong

15.1 What is a Biorefinery and What is the Difference with an Oil Refinery? 470

15.2 Types of Biorefineries 474

15.3 Economic Considerations Evaluating Biorefinery Concepts: Basic Methods for Assessing Investments and Cost Prices 481

15.4 Outlook to the Future of Biorefineries 492

Chapter Summary and Study Guide 493

Key Concepts 493

Short-Answer Questions 493

Problems 494

Projects 497

Internet References 500

References 500

PART IV END USES 503

16 High-Efficiency Energy Systems with Biomass Gasifiers and Solid Oxide Fuel Cells 505
P.V. Aravind and Ming Liu

16.1 Introduction 506

16.2 Solid Oxide Fuel Cells 507

16.3 Biomass Gasifier–SOFC Combination 512

16.4 Concluding Remarks 520

Chapter Summary and Study Guide 520

Key Concepts 521

Short-Answer Questions 521

Problems 521

Projects 522

Internet References 522

References 523

17 Synthesis Gas Utilization for Transportation Fuel Production 525
J. Ruud van Ommen and Johan Grievink

17.1 Introduction 526

17.2 Fischer–Tropsch Synthesis 527

17.3 Synthetic Natural Gas Synthesis 535

17.4 Methanol Synthesis 537

17.5 Comparison of the Different Options 538

Chapter Summary and Study Guide 540

Key Concepts 540

Short-Answer Questions 541

Problems 541

Projects 544

Internet References 545

References 545

18 Chemistry of Biofuels and Biofuel Additives from Biomass 547
Isabel W.C.E. Arends

18.1 Introduction 548

18.2 Bioethanol and Biodiesel 548

18.3 Conversion of Sugars to Hydrocarbon Fuels 553

18.4 Greenness of the Conversion of Platform Molecules into Biobased Fuel Additives 557

18.5 Direct Aqueous Reforming of Sugars Leading to a Range of Alkanes 564

18.6 Future Generations of Biofuel 566

Chapter Summary and Study Guide 566

Key Concepts 567

Short-Answer Questions 567

Problems 568

Projects 568

Internet References 568

References 569

INDEX 571

Wiebren de Jong is an associate professor at Delft University of Technology working in the Process & Energy department. He is involved as senior researcher in several EU and national projects concerning biomass pretreatment, combustion, gasification and biorefinery processes. He is co-author of more than 65 journal papers concerning thermal and chemical conversion of biomass.