Modern Drying Technology, Experimental Techniques (Volume 2)

✍ Scribed by Evangelos Tsotsas, Arun S. Mujumdar

• Publisher: Wiley-VCH
• Year: 2009
• Tongue: English
• Leaves: 414
• Edition: Volume 2
• Category: Library

✦ Synopsis

Volume two of a five-volume handbook that provides a comprehensive overview of all important aspects of modern drying technology, presenting high-level, cutting-edge results.Volume 2 comprises modern experimental techniques such as magnetic resonance imaging for measurement and visualisation of moisture profiles in the interior of porous bodies during drying, Raman spectroscopy for measurement of concentration profiles during the drying of thin films/coatings and analytical methods for measurement of drying kinetics. Other modern experimental techniques covered include sorption equilibria and moisture content of individual particles, techniques for the determination of important quality indices - functional and structural properties - of dried products and instrumentation of modern drying equipment and respective plants.

✦ Table of Contents

Modern Drying Technology Volume- 2......Page 5
Contents......Page 7
Series Preface......Page 15
Preface of Volume 2......Page 19
List of Contributors......Page 25
Recommended Notation......Page 29
EFCE Working Party on Drying: Address List......Page 35
1.1 Introduction and Overview......Page 41
1.2.1 Determination of Single Particle Drying Kinetics – General Remarks......Page 42
1.2.2 Configuration and Periphery of Magnetic Suspension Balance......Page 44
1.2.3 Discussion of Selected Experimental Results......Page 46
1.3.1 Measurement for Particle Systems – General Remarks......Page 50
1.3.2 Experimental Set-Up......Page 52
1.3.3 Principle of Measurement with the Infrared Spectrometer......Page 53
1.3.4 Dew Point Mirror for Calibration of IR Spectrometer......Page 54
1.3.5 Testing the Calibration......Page 57
1.3.6 A Case Study: Determination of Single Particle Drying Kinetics of Powdery Material......Page 60
1.4.1 Particle Moisture as a Distributed Property......Page 64
1.4.2 Modeling the Distribution of Solids Moisture at the Outlet of a Continuous Fluidized Bed Dryer......Page 65
1.4.3 Challenges in Validating the Model......Page 67
1.4.4 Coulometry......Page 68
1.4.5 Nuclear Magnetic Resonance......Page 73
1.4.7 Experimental Moisture Distributions and Assessment of Model......Page 77
1.5.1 Introductory Remarks......Page 81
1.5.2 Some Useful Definitions......Page 82
1.5.3 Forces in a Standing Acoustic Wave......Page 83
1.5.4 Interactions of a Droplet with the Sound Pressure Field......Page 87
1.5.4.2 Primary and Secondary Acoustic Streaming......Page 88
1.5.4.3 Effects of Changing Droplet Size......Page 93
1.5.5.1 Drying Rate of a Spherical Solvent Droplet......Page 95
1.5.5.3 Drying Rate of Droplets of Solutions or Suspensions......Page 98
1.5.6 A Case Study: Single Droplet Drying of Water and an Aqueous Carbohydrate Solution......Page 99
1.5.6.1 A Typical Acoustic Levitator......Page 100
1.5.6.2 Evaporation Rates of Acoustically-Levitated Pure Water Droplets......Page 101
1.5.6.3 Evaporation Rates and Particle Formation with Aqueous Mannitol Solution Droplets......Page 103
1.6 Concluding Remarks......Page 106
References......Page 109
2.1 Introduction......Page 113
2.2.2 Lambert–Beer Law......Page 114
2.2.3 Hyperspectrum......Page 116
2.2.4 Classification by Spectral Information Acquisition Technique......Page 117
2.2.5 Classification by Spatial Information Acquisition Technique......Page 118
2.3.2 Noise and Shading Correction......Page 119
2.3.3 Conversion into Absorbance Image......Page 120
2.3.4 Acquisition and Pretreatment of Spectral Data......Page 121
2.3.6 Visualization of Constituent Distribution......Page 122
2.4.1.1 Imaging Apparatus......Page 123
2.4.1.3 Spectral Analysis......Page 124
2.4.2.1 Sample......Page 125
2.4.2.3 Spectral Analysis......Page 126
2.4.2.4 Visualization of Moisture Distribution......Page 127
2.5 Future Outlook......Page 128
References......Page 129
3.1 Introduction......Page 131
3.2.1 General Considerations......Page 133
3.2.2.2 Net Magnetization and Radio Frequency Excitation......Page 134
3.2.2.3 Relaxation and NMR Signal......Page 135
3.2.3 Imaging Principles......Page 137
3.2.3.2 Two-Dimensional Imaging......Page 138
3.2.3.3 Slice Selection......Page 139
3.2.3.4 Three-Dimensional Imaging......Page 140
3.2.4.1 The Spin–Echo (SE) Sequence......Page 141
3.3.1 Some General Data about the Materials......Page 142
3.3.2.1 Pulp, Paper and Cellulose Samples......Page 144
3.3.2.2 Wood......Page 146
3.3.3.1 Experimental Conditions......Page 148
3.3.3.2 Drying Experiments and MRI Parameters......Page 149
3.3.3.3 Calibration Procedure......Page 151
3.3.3.4 Results for Drying Profiles......Page 154
3.3.3.5 Diffusion Measurements......Page 159
3.4.1 MRI and Transport Phenomena in Agricultural and Food Products......Page 165
3.4.2 NMR for Characterization of Biological and Food Products......Page 166
3.4.3.1 General Data......Page 168
3.4.3.2 Measurement of Moisture Profiles in a Gel during Drying......Page 170
3.4.4.2 NMR Preliminary Experiments......Page 172
3.4.4.3 NMR Imaging Experiments......Page 174
3.4.4.5 Imaging Results and Moisture Profiles......Page 175
3.5 Conclusion......Page 177
References......Page 179
4.1.1 Introduction......Page 183
4.1.2 Physical Principles......Page 184
4.1.3 Reconstruction......Page 188
4.2.1 Geometry of CT Systems......Page 193
4.2.2 X-Ray Macrotomography (or Industrial Tomography)......Page 195
4.2.3 X-Ray Microtomography......Page 196
4.3.1 Algorithms for 3D Image Filtering and Segmentation......Page 197
4.3.2 Calculation of Morphological Characteristics......Page 203
4.3.2.2 Cluster Volume Distribution......Page 204
4.3.2.3 Percolation......Page 205
4.3.2.5 Interface Curvature......Page 206
4.4.1.1 Sludge Individual Extrudates......Page 207
4.4.1.2 Sludge Packed Bed......Page 210
4.4.2 Drying Optimization of Resorcinol-Formaldehyde Xerogels......Page 213
4.4.3.1 Experimental Set-Up......Page 216
4.4.3.2 Spatio-Temporal Evolution of the Drying Front......Page 217
4.5 Future Outlook......Page 220
References......Page 222
5.1 Introduction......Page 227
5.2.1.1 Measuring Principle......Page 228
5.2.1.2 Instrumentation......Page 229
5.2.1.3 Applications......Page 230
5.2.2.1 Measuring Principle......Page 234
5.2.2.2 Measurement Results: Size and Shape......Page 236
5.3.1 Introduction......Page 241
5.3.2 Particle Detection......Page 242
5.3.3 Particle Image Velocimetry......Page 248
5.3.4 Spectral Analysis of Pressure Drop Fluctuations......Page 258
5.3.5 Positron Emission Particle Tracking......Page 263
5.3.5.1 Particle Circulation Time......Page 264
5.3.6 Fiber Optical Probe Measurement Technique......Page 268
5.3.6.1 Calibration......Page 271
5.3.6.2 Experimental Results......Page 272
5.4.1 Introduction......Page 276
5.4.2.1 Theory......Page 277
5.4.2.2 Experimental Results......Page 280
5.4.3.1 Lorentz–Mie Theory as Measuring Principle......Page 283
5.4.3.2 Measurement in High Concentrations with Small Optical Measuring Volume......Page 284
5.4.3.3 Calibration and Evaluation......Page 286
5.4.3.4 Experimental Results......Page 289
5.5.1 Introduction......Page 291
5.5.2.1 Mechanical Interactions......Page 292
5.5.2.2 Adhesive Interactions......Page 294
5.5.2.3 Cohesive Interactions......Page 296
5.5.2.4 Frictional and Lubrication Interactions......Page 299
5.5.3 Mechanical Properties of Wet Granular Media......Page 301
5.5.3.1 Elastoplastic Measurements......Page 302
5.5.3.2 Failure Properties......Page 306
5.6 Conclusions......Page 309
References......Page 312
6.1 Introduction to Common Particle Properties......Page 319
6.2.1 Image Analysis by Optical and Scanning Electron Microscopy......Page 320
6.2.1.2 Electron Microscopy......Page 321
6.2.1.3 Image Analysis......Page 322
6.2.2 Laser Light Scattering and Diffraction for Dilute Particle Dispersions......Page 323
6.2.3.1 Acoustic Attenuation Spectroscopy......Page 331
6.2.3.2 Electrokinetic Sonic Amplitude Spectroscopy......Page 332
6.3.1.1 Introduction......Page 333
6.3.1.2 Volume Determination Using Gas Pycnometry......Page 334
6.3.2.1 Physical Principles......Page 336
6.3.2.2 Surface Area Determination using the BET-Model......Page 338
6.3.3.1 Introduction......Page 340
6.3.3.2 Assessment of Microporosity......Page 341
6.3.3.3 Assessment of Mesoporosity......Page 342
6.3.3.4 Simplified Assessment of Pore Volume......Page 344
6.3.3.5 Measurement Set-Up and Test Method......Page 345
6.3.4.1 Particle Adhesion Effects......Page 347
6.3.4.2 Comparison between Different Adhesion Forces......Page 348
6.3.4.3 Survey of Adhesion Force Test Methods......Page 349
6.3.4.4 Particle Interaction Apparatus According to Butt......Page 350
6.3.5 Measurement of Particle Restitution Coefficient......Page 352
6.3.6.1 Survey of Test Methods and Principles......Page 358
6.3.6.2 Compression Test......Page 361
6.3.6.3 Impact Test......Page 365
6.4.1 Bulk Density and Tapping Density......Page 368
6.4.3 Flow Behavior of Cohesive and Compressible Bulk Solids......Page 369
6.4.4 Flow Criteria of Preconsolidated Cohesive Powders on a Physical Basis......Page 372
6.4.5 Translational Shear Cell according to Jenike......Page 375
6.4.5.1 The Shear Testing Technique SSTT according to ICE......Page 377
6.4.6 Ring Shear Tester according to Schulze for Dry Powder......Page 379
6.4.7 Press Shear Cell according to Reichmann for Wet Filter Cake......Page 380
6.4.8.2 The Uniaxial Tester according to Enstad......Page 384
6.4.8.4 Powder Flow Analyzer ShearScan TS12 by AnaTec......Page 386
6.5 Measurement of Particle Bed Movement in Rotary Drums by High-Speed Camera......Page 388
6.6 Conclusions......Page 393
References......Page 396
Index......Page 403