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Gas Cyclones and Swirl Tubes Principles, Design, and Operation

:	Alex C. Hoffmann, Louis E. Stein
:	Gas Cyclones and Swirl Tubes Principles, Design, and Operation
:	Springer-Verlag
:	9783540746966
:	2
:	CHF 321,10
:

:	Chemische Technik
:	English

:	422
:	Wasserzeichen
:	PC/MAC/eReader/Tablet
:	PDF

Believed to be a publishing first when originally brought out, this book covers all aspects of centrifugal gas cleaning devices. These are cyclones used as gas-solid separators for dedusting and as gas-liquid separators for demisting. The optimization of cyclone performance for any given task is a sought-after goal - but it is one that is seldom achieved in practice. This second edition will help mechanical and chemical engineers to achieve this optimization.

	Preface	6
	Foreword to the First Edition	10
	Foreword to the Second Edition	13
	Acknowledgments	15
	About the Authors	17
	Contents	18
	1 Introduction	24
	1.1 Some Historical Background	24
	1.2 Removal of Particles from Gases	29
	1.3 A Closer Look at Centrifugal Gas Cleaning Devices	35
	2 Basic Ideas	45
	2.1 Gas Flow	45
	2.2 Particle Motion	49
	2.3 Particle Size	54
	2.4 Particle Density	59
	2.A Ideal Vortex Laws from the Navier-Stokes Equations	60
	2.B Common Model Functions for Particle Size Distributions	63
	3 How Cyclones Work	66
	3.1 Flow in Cyclones	66
	3.2 Separation Efficiency	72
	3.3 Pressure Drop	75
	3.A Worked Example: Calculating a Grade-Efficiency Curve	77
	4 Cyclone Flow Pattern and Pressure Drop	80
	4.1 Discussion	80
	4.2 Models for the Flow Pattern	85
	4.3 Models for the Pressure Drop	91
	4.4 Model Assumptions in Light of CFD and Experiment	99
	4.5 Overview	103
	4.A Worked Example for Calculating Cyclone Pressure Drop	104
	4.B The Meissner and Löffler Model	106
	5 Cyclone Separation Efficiency	109
	5.1 Discussion	109
	5.2 Models	110
	5.3 Comparison of Model Predictions with Experiment.	117
	5.4 Overview	122
	5.A Worked Example for the Prediction of Cyclone Separation Performance	123
	5.B The Cyclone Efficiency Models of Dietz and of Mothes and Löffler	126
	6 The Muschelknautz Method of Modeling	130
	6.1 Basis of the Model	131
	6.2 Computation of the Inner Vortex Cut-Point, x50	137
	6.3 Computation of Efficiency at Low Solids Loadings	139
	6.4 Determining if the Mass Loading Effect will Occur	141
	6.5 Overall Separation Efficiency when co	141
	141	141
	6.6 Computation of Pressure Drop	143
	6.A Example Problems	144
	6.B Incorporation of the ‘Inner Feed’	152
	7 Computational Fluid Dynamics	157
	7.1 Simulating the Gas Flow Pattern	158
	7.2 Simulating the Particle Flow	165
	7.3 Some Simulations of the Gas and Particle Flow in Cyclones	167
	7.A Transport Equations	179
	8 Dimensional Analysis and Scaling Rules	181
	8.1 Classical Dimensional Analysis	182
	8.2 Scaling Cyclones in Practice	186
	8.A Inspecting the Equations of Motion	194
	8.B Sample Cyclone Scaling Calculations	195
	9 Other Factors Influencing Performance	201
	9.1 The Effect of Solids Loading	201
	9.2 The Effect of the Natural Vortex Length	213
	9.A Predicting the Effect of Solids Loading on Cyclone Efficiency	223
	9.B Predicting the Effect of Loading on Cyclone Pressure Drop	226
	10 Measurement Techniques	230
	10.1 Gas Flow Pattern	233
	10.2 Pressure Drop	235
	10.3 Particle Flow	236
	10.4 Overall Separation Efficiency	237
	10.5 Grade-Efficiency	241
	10.A Estimate of Errors	248
	11 Underflow Configurations and Considerations	251
	11.1 Underflow Configurations	251
	11.2 Importance of a Good Underflow Seal	255
	11.3 Upsets Caused by ‘Too Good’ an Underflow Seal	259
	11.4 Second-Stage Dipleg Solids ‘Backup’	262
	11.5 Hopper ‘Crossflow’	264
	11.6 Hopper Venting Options	266
	11.A Dipleg Calculation	269
	11.B Moment Balance on Flapper Valve Plate	269
	12 Some Special Topics	273
	12.1 Cyclone Erosion	273
	12.2 Critical Deposition Velocity	295
	12.3 High Vacuum Case	297
	12.A Worked Example for Calculation of the Critical Deposition Velocity	299
	12.B Worked Example Taking Into Account Slip in Calculation of the Cut Size	299
	13 Demisting Cyclones	303
	13.1 Liquid Creep and ‘Layer Loss’	304
	13.2 Demisting Cyclone Design Considerations	306
	13.3 Some Vapor-Liquid Cyclone Design Geometries and Features	308
	13.4 Estimating Inlet Drop Size for Two-Phase Mist- Annular Flow	315
	13.5 Modeling the Performance of Vapor-Liquid Cyclones	318
	13.6 Criteria for Determining if ‘Mass loading’ (‘ Saltation’) Occurs	319
	13.7 Re-entrainment From Demisting Cyclones	321
	13.A Example Calculations of Droplet Sizes in Pipe Flow	327
	13.B Flow Distribution in Parallel Demisting Cyclones	328
	13.C Method for Estimating Wall Film Thickness and Velocity	334
	13.D Example calculation	340
	14 Foam-Breaking Cyclones	343
	14.1 Introduction	343
	14.2 Some Design Considerations and Factors Influencing Behavior	346
	14.3 Applications	350
	14.4 Estimating Submergence Required to Prevent Gas ‘ Blow Out’	350
	14.A Example Computation of Submergence Required to Prevent Underflow Gas ‘ Blow Out’	356
	15 Design Aspects	357
	15.1 Cylinder-on-Cone Cyclones with Tangential Inlet	357
	15.2 Design of Swirl Tubes with Swirl Vanes	384
	15.A Example Calculation of the Throat Area	389
	15.B Construction of a Vane Cut-out Pattern of an Orthogonal Vane Assembly	390
	16 Multicyclone Arrangements	397
	16.1 Cyclones in Series	397
	16.2 Cyclones in Parallel	398
	16.A Example Calculation for Multicyclone Arrangements	407
	17 List of Symbols	412
	List of Tradenames	418
	References	419
	Index	424