Introduction to Chemical Engineering

C.M. van ’t Land ran the seminar and consulting company Van ’t Land Processing between 1999 and 2020. Prior to that, he worked at Akzo Nobel Chemicals from 1968-2000 as process engineer, and later, process development manager and project leader. He is the author of Industrial Drying Equipment: Selection and Application, Industrial Crystallization of Melts, Drying in the Process Industry, and Safety in Design.

Preface xvii

Prologue xix

Part I Transport Phenomena 1

1 Mass Balances 3

1.1 Introduction 3

1.2 Theory 5

1.3 Additional Material 9

Reference 10

2 Energy Balances 11

2.1 Definitions 11

2.2 The General Energy Balance 12

2.3 Applications of the General Energy Balance 13

2.3.1 Pump 13

2.3.2 Air Oxidation of Cumene 14

2.4 The Mechanical Energy Equation 17

2.5 Applications of the Mechanical Energy Balance 18

References 22

3 Viscosity 23

3.1 Definition 23

3.2 Newtonian Fluids 25

3.3 Non-Newtonian Fluids 25

3.3.1 The Viscosity is a Function of the Temperature and the Shear Rate 25

3.3.2 The Viscosity is a Function of Time 28

3.4 Viscoelasticity 29

3.5 Viscosity of Newtonian Fluids 29

3.5.1 Gases 29

3.5.2 Liquids 30

References 32

4 Laminar Flow 33

4.1 Steady-state Flow Through a Circular Tube 33

4.2 Rotational Viscosimeters 37

4.3 Additional Remarks 39

5 Turbulent Flow 41

5.1 Velocity Distribution 41

5.2 The Reynolds Number 42

5.3 Pressure Drop in Horizontal Conduits 42

5.4 Pressure Drop in Tube Systems 45

5.5 Flow Around Obstacles 47

5.5.1 Introduction 47

5.5.2 Dispersed Spherical Particles 48

5.6 Terminal Velocity of a Swarm of Particles 53

5.7 Flow Resistance of Heat Exchangers with Tubes 53

References 54

6 Flow Meters 57

6.1 Introduction 57

6.2 Fluid-energy Activated Flow Meters 57

6.2.1 Oval-gear Flow Meter 57

6.2.2 Orifice Meter 57

6.2.3 Venturi Meter 60

6.2.4 Rotameter 60

6.3 External Stimulus Flow Meters 61

6.3.1 Thermal Flow Meter 61

6.3.2 Ultrasonic Flow Meters 62

References 62

7 Case Studies Flow Phenomena 63

7.1 Energy Consumption: Calculation of the Power Potential of a High Artificial Lake 63

7.2 Estimation of the Size of a Pump Motor 64

8 Heat Conduction 67

8.1 Introduction 67

8.2 Thermal Conductivity 68

8.3 Steady-state Heat Conduction 71

8.4 Heating or Cooling of a Solid Body 75

References 78

9 Convective Heat Transfer 79

9.1 Heat Exchangers 79

9.2 Heat Transfer Correlations 84

References 86

10 Heat Transfer by Radiation 87

10.1 Introduction 87

10.2 IR 87

10.3 Dielectric Heating 91

10.3.1 General Aspects 91

10.3.2 RF Heating 93

10.3.3 Microwave Heating 94

References 97

11 Case Studies Heat Transfer 99

11.1 Bulk Materials Heat Exchanger 99

11.2 Heat Exchanger 100

11.3 Surface Temperature of the Sun 102

11.4 Gas IR Textile Drying 102

11.5 Heat Loss by IR Radiation 103

11.6 Microwave Drying of a Pharmaceutical Product 103

References 104

12 Steady-state Diffusion 105

12.1 Introduction and Definition of the Diffusion Coefficient 105

12.2 The Diffusion Coefficient 106

12.3 Steady-state Diffusion 107

References 112

13 Convective Mass Transfer 113

13.1 Partial and Overall Mass Transfer Coefficients 113

13.2 Mass Transfer Between a Fixed Wall and a Flowing Medium 116

13.3 Simultaneous Heat and Mass Transfer at Convective Drying 118

References 121

14 Case Studies Mass Transfer 123

14.1 Equimolar Diffusion 123

14.2 Diffusion through a Stagnant Body 123

14.3 Sublimation of a Naphthalene Sphere 124

Reference 126

Notation I 127

Greek Symbols 131

Part II Mixing and Stirring 135

15 Introduction to Mixing and Stirrer Types 137

References 142

16 Mixing Time 143

16.1 Introduction 143

16.2 Approach of Beek et al. 144

16.3 Approach of Zlokarnik 147

References 151

17 Power Consumption 153

References 156

18 Suspensions 157

18.1 Introduction 157

18.2 Power Consumption 162

18.3 Further Work 163

References 164

19 Liquid/Liquid Dispersions 165

Reference 167

20 Gas Distribution 169

20.1 Introduction 169

20.2 Turbine 169

20.3 Pitched-Blade Turbine Pumping Downward 175

20.4 Turbine Scale Up 176

20.5 Batch Air Oxidation of a Hydrocarbon 177

20.6 Remark 178

Appendix 20.1 178

References 179

21 Physical Gas Absorption 181

21.1 Introduction 181

21.2 k l . a Measurements 181

21.3 Power Consumption on Scaling Up 184

21.4 Remarks 184

References 184

22 Heat Transfer in Stirred Vessels 185

22.1 Introduction 185

22.2 Heat Transfer Jacket Wall/Process Liquid 185

22.3 Heat Transfer Coil Wall/Process Liquid 188

22.4 Heat Transfer Jacket Medium/Vessel Wall 190

22.5 Heat Transfer Coil Medium/Coil Wall 192

22.6 Batch Heating and Cooling 192

References 193

23 Scale Up of Mixing 195

23.1 Introduction 195

23.2 Homogenization 196

23.3 Suspensions 198

23.4 Liquid/Liquid Dispersions 198

23.5 Gas Distribution 198

23.6 k l . a 198

23.7 Heat Transfer 199

References 199

24 Case Studies Mixing and Stirring 201

24.1 Mixing Time—Comparison of Stirrers 201

24.2 Mixing Time—Scale Up of Process 202

24.3 Suspensions 202

24.4 Air Oxidation Optimization 203

24.5 Calculating k l . a 205

24.6 Heating Toluene in a Stirred Vessel 206

24.7 Overall Heat Transfer Coefficient of a Jacketed Reactor 207

24.8 Scale Up of Mixing 209

References 210

Notation II 211

Greek Symbols 213

Part III Chemical Reactors 215

25 Chemical Reaction Engineering—An Introduction 217

25.1 Fluidized Catalytic Cracking (FCC) 217

25.2 Kinetic Rate Data and Transport Phenomena 218

25.3 Reactor Types 219

25.4 Batch Reactions Versus Continuous Reactions 221

25.5 Adiabatic Temperature Rise 222

25.6 Recycle 223

25.7 Process Intensification 224

References 226

26 A Few Typical Chemical Reactors 227

26.1 The Carbo-V-Process of Choren 227

26.2 Coal Gasification 227

26.3 Biofuels 229

26.4 Pyrogenic Silica 230

26.5 Microwaves 231

27 The Order of a Reaction 233

27.1 The Rate of a Reaction 233

27.2 Introductory Remarks on the Order of a Reaction 233

27.3 First-Order Reaction 234

27.4 Second-Order Reactions 236

References 239

28 The Rate of Chemical Reactions as a Function of Temperature 241

28.1 Arrhenius’ Law 241

28.2 How to Influence Chemical Reaction Rates 242

Reference 243

29 Chemical Reaction Engineering—A Quantitative Approach 245

29.1 Introduction 245

29.2 Batch Reactor 245

29.3 Plug Flow Reactor 247

29.4 Continuous Stirred Tank Reactor (CSTR) 248

29.5 Reactor Choice 251

29.6 Staging 251

29.7 Reversible Reactions 253

30 A Plant Modification: From Batchwise to Continuous Manufacture 257

30.1 Introduction 257

30.2 Batchwise Production 257

30.3 Continuous Manufacture 257

Reference 258

31 Intrinsic Continuous Process Safeguarding 259

31.1 Summary 259

31.2 Introduction 259

31.3 The Production of Organic Peroxides 260

31.4 Intrinsically Safe Processes 260

31.5 Intrinsic Process Safeguarding 261

31.6 Extrinsic Process Safeguarding 261

31.7 Additional Remarks 261

31.8 Practical Approach 262

31.9 Examples 263

References 265

32 Reactor Choice and Scale Up 267

32.1 Introduction 267

32.2 Parallel Reactions 267

32.3 Physical Effects 269

33 Case Studies Chemical Reaction Engineering 271

33.1 Order of a Reaction 271

33.2 Chemical Reaction Rate as a Function of Temperature 273

33.3 Reactor Size 273

33.4 Reversible Reactions 274

33.5 Competing Reactions 276

33.6 The Hydrolysis of Acetic Acid Anhydride 276

33.7 Cumene Air Oxidation 277

References 278

Notation III 279

Greek Symbols 280

Part IV Distillation 281

34 Continuous Distillation 283

34.1 Introduction 283

34.2 Vapor–Liquid Equilibrium 283

34.3 The Fractionating Column 286

34.4 The Number of Trays Required 288

34.5 The Importance of the Reflux Ratio 292

34.6 A Typical Continuous Industrial Distillation 293

References 294

35 Design of Continuous Distillation Columns 295

35.1 Sieve Tray Columns 295

35.2 Packed Columns 299

Note 302

References 302

36 Various Types of Distillation 303

36.1 Batch Distillation 303

36.2 Azeotropic and Extractive Distillation 309

36.3 Steam Distillation 311

References 312

37 Case Studies Distillation 313

37.1 McCabe–Thiele Diagram 313

37.2 Diameter of a Sieve Tray Column and Sieve Tray Pressure Loss 316

37.3 The Distillation of Wine 317

37.4 Steam Distillation 320

Reference 321

Notation IV 323

Greek Symbols 325

Part V Liquid Extraction 327

38 Liquid Extraction – Part 1 329

38.1 Introduction 329

38.2 The Distribution Coefficient 333

38.3 Calculation of the Number of Theoretical Stages in Extraction Operations 334

References 336

39 Liquid Extraction – Part 2 337

39.1 Calculation of the Number of Transfer Units in Extraction Operations 337

Reference 342

40 Flooding 343

40.1 General 343

References 345

41 The Two Liquids Exchanging a Component Are Partially Miscible 347

41.1 Triangular Coordinates 347

41.2 Formation of One Pair of Partially Miscible Liquids 348

41.3 Continuous Countercurrent Multiple-contact Extraction 353

References 355

42 Case Studies Liquid Extraction 357

42.1 A Series of Centrifugal Extractors 357

42.2 Extraction by Means of An Ionic Liquid 359

42.3 Overall Transfer Coefficient/Height of a Transfer Unit 360

42.4 Calculation of the Column Height 362

42.5 Two Partially Miscible Liquids Exchange a Component 363

References 365

Notation V 367

Greek Symbols 369

Part VI Absorption of Gases 371

43 Absorption of Gases 373

43.1 Introduction 373

43.2 Determination of the Number of Theoretical Stages at Absorption of Gases 374

43.3 Estimation of the Diameter of an Absorption Column for Natural Gas 377

43.4 The Absorption of Carbon Dioxide 378

43.5 Design of Absorption Columns 379

References 381

Notation VI 383

Greek Symbols 384

Part VII Membranes 385

44 Membranes—An Introduction 387

44.1 General 387

44.2 Membranes 387

44.3 Three Pressure-Driven Membrane Separation Processes for Aqueous Systems 389

44.4 A Membrane Separation Process for Aqueous Solutions Which Is Driven by an Electrical Potential Difference 390

44.5 Gas Separation 391

44.6 Pervaporation 392

44.7 Medical Applications 392

44.8 Additional Remarks 393

References 394

45 Microfiltration 395

45.1 Introduction 395

45.2 Membrane Types 396

45.3 Membrane Characterization 397

45.4 Filter Construction 397

45.5 Operational Practice 398

References 399

46 Ultrafiltration 401

46.1 Introduction 401

46.2 Membrane Characterization 401

46.3 Concentration Polarization and Membrane Fouling 402

46.4 Membrane Cleaning 406

46.5 Ultrafiltration Membrane Systems 407

46.6 Continuous Systems 408

46.7 Applications 409

References 411

47 Reverse Osmosis 413

47.1 Osmosis 413

47.2 Reverse Osmosis 414

47.3 Theoretical Background 415

47.4 Concentration Polarization 417

47.5 Membrane Specifications 417

47.6 Membrane Qualities 417

47.7 Reverse Osmosis Units 418

47.8 Membrane Fouling Control and Cleaning 419

47.9 Applications 420

47.10 Nanofiltration Membranes 421

47.11 Conclusions and Future Directions 421

References 421

48 Electrodialysis 423

48.1 Introduction 423

48.2 Functioning of Ion-Exchange Membranes 424

48.3 Types of Ion Exchange Membranes 424

48.4 Transport in Electrodialysis Membranes 425

48.5 Power Consumption 427

48.6 System Design 427

48.7 Applications 428

References 429

49 Gas Separation 431

49.1 Introduction 431

49.2 Theoretical Background 431

49.3 Process Design 436

49.4 Applications 437

References 441

50 Case Studies Membranes 443

50.1 Gel Formation 443

50.2 Osmotic Pressure 443

50.3 Membrane Gas Separation 444

References 445

Notation VII 447

Greek Symbols 448

Part VIII Crystallization, Liquid/Solid Separation, and Drying 449

51 Crystallization 451

51.1 Introduction 451

51.2 Solubility 451

51.3 Nucleation 452

51.4 Crystal Growth 453

51.5 Crystallizers and Crystallizer Operations 454

51.6 The Population Density Balance 457

51.7 Interpretation of the Results of Population Density Balances 463

References 466

52 Liquid/Solid separation 467

52.1 Introduction 467

52.2 Filtration 467

52.2.1 Introduction 467

52.2.2 Cake Filtration 468

52.2.3 Filter Aids 471

52.2.4 Deep-Bed Filtration 472

52.2.5 Filtration Equipment 472

52.3 Centrifugation 475

Reference 478

53 Convective Drying 479

53.1 Introduction 479

53.2 Four Important Continuous Convective Dryers in the Chemical Industry 480

53.3 A First Example of Convective Drying 482

53.4 The Adiabatic Saturation Temperature 483

53.5 The Wet-Bulb Temperature 485

53.6 The Mollier Diagram 486

53.7 Drying Vacuum Pan Salt in a Plug Flow Fluid-Bed Dryer 488

54 Design of a Flash Dryer 489

54.1 Introduction 489

54.2 Design 489

Reference 491

55 Contact Drying 493

55.1 Introduction 493

55.2 Scaling Up of a Conical Vacuum Dryer 493

55.3 An Additional Remark Concerning Vacuum Drying 497

55.4 Testing a Small Plate Dryer 498

55.5 Testing a Continuous Paddle Dryer 500

55.6 Scale Up of a Thin-Film Dryer 503

Reference 506

56 Case Studies Crystallization, Liquid/Solid Separation, and Drying 507

56.1 Ultracentrifuges 507

56.2 Le 2/3 507

56.3 Convective Drying- 1 508

56.4 Convective Drying- 2 509

56.5 Analysis of a Spray-Drying Operation 509

56.6 Estimation of the Size of a Contact Dryer 512

References 515

Notation VIII 517

Greek Symbols 519

Part IX Gas/Solid Separation 521

57 Introduction 523

58 Cyclones 525

58.1 Introduction 525

58.2 Sizing and Process Data 525

References 527

59 Fabric Filters 529

59.1 Introduction 529

59.2 Fabrics 529

59.3 Baghouse Construction and Operation 531

Reference 532

60 Scrubbers 533

60.1 Introduction 533

60.2 Packed-Bed Scrubbers 534

60.3 Venturi Scrubbers 535

60.4 Mechanical Scrubbers 536

References 537

61 Electrostatic Precipitators 539

61.1 Introduction 539

61.2 Principle of Operation 540

61.3 Process Data 540

61.4 Construction 540

Reference 542

Notation IX 543

Greek Symbols 543

Index 545