Progress in Filtration and Separation

1. Auflage 2014
ISBN: 978-0-12-398307-7
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 698 Seiten

Progress in Filtration and Separation contains reference content on fundamentals, core principles, technologies, processes, and applications. It gives detailed coverage of the latest technologies and research, models, applications and standards, practical implementations, case studies, best practice, and process selection. Extensive worked examples are included that cover basic calculations through to process design, including the effects of key variables. Techniques and topics covered include pervaporation, electrodialysis, ion exchange, magnetic (LIMS, HIMS, HGMS), ultrasonic, and more. - Solves the needs of university based researchers and R&D engineers in industry for high-level overviews of sub-topics within the solid-liquid separation field - Provides insight and understanding of new technologies and methods - Combines the expertise of several separations experts

Autoren/Hrsg.

Inhaltsverzeichnis

1;Front
Cover;1
2;Progress in Filtration and Separation;4
3;Copyright;5
4;CONTENTS;6
5;LIST OF CONTRIBUTORS;16
6;Chapter One - Hydrocyclones;20
6.1;NOMENCLATURE;21
6.2;1. BACKGROUND;22
6.3;2. BASIC DESIGN;24
6.4;3. CHARACTERIZATION OF PERFORMANCE;26
6.5;4. HYDROCYCLONE MODELS;28
6.6;5. SCALE-UP AND DESIGN;34
6.7;6. MONITORING AND CONTROL OF HYDROCYCLONES;35
6.8;7. FUTURE DEVELOPMENTS;38
6.9;REFERENCES;39
7;Section 1 Membrane filters;44
7.1;Chapter two - Dynamic Filtration with Rotating Disks, and Rotating or Vibrating Membranes;46
7.1.1;1. INTRODUCTION;47
7.1.2;2. REVIEW OF INDUSTRIAL DYNAMIC FILTRATION MODULES;50
7.1.3;3. CALCULATIONS OF INTERNAL FLUID DYNAMICS IN VARIOUS DYNAMIC FILTRATION MODULES;59
7.1.4;4. RECENT APPLICATIONS OF DYNAMIC FILTRATION AND INDUSTRIAL CASE STUDIES;61
7.1.5;5. DISCUSSION;73
7.1.6;6. CONCLUSIONS;75
7.1.7;REFERENCES;75
7.2;Chapter three - Membrane Distillation (MD);80
7.2.1;1. MEMBRANE DISTILLATION SEPARATION TECHNOLOGY AND ITS VARIANTS;81
7.2.2;2. MD MODULES AND FLUID FLOW;90
7.2.3;3. MD APPLICATIONS: FILTRATION AND SEPARATION;102
7.2.4;4. TIPS, REMARKS, AND FUTURE DIRECTIONS IN MD;110
7.2.5;Acknowledgments;111
7.2.6;REFERENCES;111
7.3;Chapter Four - Pervaporation;120
7.3.1;1. INTRODUCTION;120
7.3.2;2. FUNDAMENTALS OF PERVAPORATION;125
7.3.3;3. PERVAPORATION MEMBRANES;134
7.3.4;4. HYDROPHILIC PERVAPORATION: APPLICATIONS IN DEHYDRATION;140
7.3.5;5. HYDROPHOBIC PERVAPORATION;146
7.3.6;6. ORGANOPHILIC PERVAPORATION;148
7.3.7;7. HYBRID SYSTEMS;149
7.3.8;8. ETHANOL PURIFICATION AND PRODUCTION OF BIO-ETHANOL;154
7.3.9;9. PERVAPORATION MEMBRANE REACTORS;158
7.3.10;10. CONCLUSIONS;162
7.3.11;REFERENCES;163
7.4;Chapter Five - Liquid – Membrane Filters;174
7.4.1;1. INTRODUCTION;175
7.4.2;2. THEORETICAL BACKGROUND OF SOLUTE TRANSPORT THROUGH LM;176
7.4.3;3. MECHANISM OF TRANSPORT OF SOLUTE IN LM-BASED SEPARATION;178
7.4.4;4. TYPES OF TRANSPORT OF SOLUTE IN LM-BASED SEPARATION;181
7.4.5;5. CARRIER;185
7.4.6;6. SOLVENTS;189
7.4.7;7. TYPES OF LM;190
7.4.8;8. OPERATIONAL ISSUES RELATED TO LM-BASED SEPARATION UNIT;200
7.4.9;9. CASE STUDY;202
7.4.10;REFERENCES;221
7.5;Chapter Six - Electrodialysis;226
7.5.1;1. INTRODUCTION;227
7.5.2;2. ELECTRODIALYZER;229
7.5.3;3. CONTINUOUS (SINGLE-PASS) ELECTRODIALYSIS PROGRAM;237
7.5.4;4. BATCH ELECTRODIALYSIS PROGRAM;267
7.5.5;5. FEED-AND-BLEED ELECTRODIALYSIS PROGRAM;285
7.5.6;REFERENCES;301
8;Section 2 Force field assisted separators;304
8.1;Chapter Seven - Magnetic Techniques for Mineral Processing;306
8.1.1;1. INTRODUCTION TO MAGNETIC SEPARATION;306
8.1.2;2. MAGNETIC SEPARATION TECHNIQUES;310
8.1.3;3. CASE STUDIES ON MAGNETIC SEPARATIONS;335
8.1.4;4. FUTURE TRENDS IN MAGNETIC SEPARATION;340
8.1.5;5. CONCLUSIONS;342
8.1.6;REFERENCES;342
8.1.7;LIST OF RELEVANT WEB SITES;343
8.2;Chapter Eight - Electric (Electro/Dielectro-Phoretic)—Force Field Assisted Separators;344
8.2.1;NOMENCLATURE;345
8.2.2;1. INTRODUCTION;347
8.2.3;2. ELECTROPHORETIC AND ELECTROOSMOTIC TREATMENTS;348
8.2.4;3. DIELECTROPHORETIC TREATMENT;382
8.2.5;4. COMPARISON OF ELECTRICALLY ASSISTED SEPARATION PROCESSES;406
8.2.6;5. CONCLUSIONS;409
8.2.7;REFERENCES;410
8.3;Chapter Nine - Ultrasonic;418
8.3.1;1. INTRODUCTION;418
8.3.2;2. ORIGIN OF ULTRASONICALLY INDUCED EFFECTS;419
8.3.3;3. STANDING WAVE SEPARATION;422
8.3.4;4. ULTRASOUND ASSISTED SIEVING;424
8.3.5;5. POLISHING FILTRATION;426
8.3.6;6. SLUDGE DEWATERING;430
8.3.7;7. MEMBRANE FILTRATION;434
8.3.8;REFERENCES;437
8.3.9;LIST OF RELEVANT WEB SITES;440
9;Section 3 Membranes;442
9.1;Chapter Ten - Ion Exchange;444
9.1.1;1. ION EXCHANGE PROCESS;444
9.1.2;2. ION EXCHANGE MATERIALS;491
9.1.3;3. INDUSTRIAL APPLICATIONS OF ION EXCHANGE PROCESSES;497
9.1.4;REFERENCES;506
9.2;Chapter Eleven - Hot Gas Filters;518
9.2.1;1. INTRODUCTION;518
9.2.2;2. HOT GAS FILTRATION—ADVANTAGES/DISADVANTAGES;520
9.2.3;3. FILTER MEDIA FOR HOT GAS FILTRATION;521
9.2.4;4. SURFACE FILTRATION AND HOT GAS FILTER ELEMENT CLEANING;528
9.2.5;5. HOT GAS FILTER DESIGN;536
9.2.6;6. APPLICATIONS;540
9.2.7;7. CONCLUSIONS;542
9.2.8;REFERENCES;542
9.3;Chapter Twelve - Air Tabling—A Dry Gravity Solid–Solid Separation Technique;546
9.3.1;NOMENCLATURE;547
9.3.2;1. INTRODUCTION;549
9.3.3;2. APPLICATIONS OF AIR TABLING;550
9.3.4;3. APPARATUS;551
9.3.5;4. PRINCIPLES OF AIR TABLING;553
9.3.6;5. CASE STUDY: AIR TABLING OF PVC/PP MIXTURE;560
9.3.7;6. PERFORMANCE CURVE OF AIR TABLING;572
9.3.8;REFERENCES;574
9.4;Chapter Thirteen - Gas–Gas Separation by Membranes;576
9.4.1;NOMENCLATURE;577
9.4.2;INDICES;577
9.4.3;1. INTRODUCTION;578
9.4.4;2. MEMBRANE MODULES FOR GAS SEPARATION;579
9.4.5;3. PROCESS DESIGN;587
9.4.6;4. APPLICATIONS OF GAS PERMEATION PROCESSES;593
9.4.7;REFERENCES;603
9.5;Chapter Fourteen - Surface Area: Brunauer–Emmett–Teller (BET);604
9.5.1;1. INTRODUCTION;604
9.5.2;2. GAS–SOLID INTERFACE;605
9.5.3;3. SURFACE ADSORPTION PHENOMENA;606
9.5.4;4. BET SURFACE AREA MEASUREMENTS;609
9.5.5;5. SAMPLE PREPARATION;611
9.5.6;6. VOLUMETRIC GAS ADSORPTION TECHNIQUE;613
9.5.7;7. GRAVIMETRIC DYNAMIC VAPOUR SORPTION TECHNIQUE;615
9.5.8;8. CHROMATOGRAPHIC ADSORPTION TECHNIQUE;620
9.5.9;9. SUMMARY;626
9.5.10;REFERENCES;626
9.6;Chapter Fifteen - Particle Shape Characterization by Image Analysis;628
9.6.1;NOMENCLATURE;628
9.6.2;1. INTRODUCTION;629
9.6.3;2. IMAGE ACQUISITION;630
9.6.4;3. IMAGE TREATMENT;633
9.6.5;4. BASIC SIZE DESCRIPTORS;635
9.6.6;5. SHAPE DESCRIPTORS;637
9.6.7;6. TWINNED CRYSTALS AND AGGLOMERATES;639
9.6.8;7. FRACTAL-LIKE PARTICLES;640
9.6.9;8. BIOLOGICAL PARTICLES;643
9.6.10;9. CASE OF IN SITU IMAGES;645
9.6.11;10. SELECTION OF MAGNIFICATION;647
9.6.12;11. DISTRIBUTIONS;648
9.6.13;12. 3D SHAPE;651
9.6.14;13. CONCLUSIONS;652
9.6.15;REFERENCES;653
9.7;Chapter Sixteen - Turbidity: Measurement of Filtrate and Supernatant Quality?;656
9.7.1;1. IMPORTANCE OF PARTICULATES IN PROCESS AND MUNICIPAL WATERS;656
9.7.2;2. ADVANTAGES OF TURBIDITY MEASUREMENTS;658
9.7.3;3. TURBIDITY AS SURROGATE FOR PARTICLE CONCENTRATIONS;662
9.7.4;4. PRINCIPLES OF TURBIDITY MEASUREMENT;664
9.7.5;5. TURBIDITY INSTRUMENTS;666
9.7.6;6. INSTRUMENT CALIBRATION;671
9.7.7;7. TECHNIQUES FOR ACCURATE TURBIDITY MEASUREMENTS;673
9.7.8;REFERENCES;675
9.8;Chapter Seventeen - Capillary Suction Time (CST);678
9.8.1;1. INTRODUCTION;678
9.8.2;2. METHODS;679
9.8.3;3. FACTORS AFFECTING CST MEASUREMENTS;683
9.8.4;4. EXAMPLES OF CST USE;685
9.8.5;5. CONCLUSIONS;687
9.8.6;REFERENCES;687
10;INDEX;690

Leseproben

Chapter Two

Dynamic Filtration with Rotating Disks, and Rotating or Vibrating Membranes

Luhui Ding, Michel Y. Jaffrin,  and Jianquan Luo     Technological University of Compiegne, Compiegne Cedex, France

Abstract

This article describes various systems of dynamic filtration, also called shear-enhanced filtration, which consists in creating high shear rates at the membrane by a rotating disk, or by rotating or vibrating the membranes. This mode of operation permits to reach shear rates of the order of 1–3·105/s or almost one order of magnitude larger than in crossflow filtration and to increase both permeate flux and membrane selectivity. Its advantages and drawbacks relatively to crossflow modules are presented in the introduction. Then it describes existing industrial dynamic filtration modules: the VSEP vibrating system, multicompartments systems with metal disks or rotors rotating between fixed membranes and multishaft systems with overlapping rotating ceramic membranes. Equations permitting to calculate membrane shear rates in various modules, are presented, as they govern their performance. Recent applications published in the literature in microfiltration, ultrafiltration, nanofiltration, and reverse osmosis are presented with a comparison of permeate fluxes with crossflow filtration data when available. A comparison of performances between the vibrating VSEP and a rotating disk module in microfiltration of yeast suspensions and in reverse osmosis of model dairy effluent is also presented. The discussion is focused on energetic considerations and the complementarity between crossflow and dynamic filtration.

Keywords

Complementarity with; crossflow filtration; High shear filtration; Rotating disks; Rotating membranes; Vibrating membranes

Contents

1. Introduction 28

1.1 Differences between Dynamic and Crossflow Filtration 29

1.2 Advantages and Limitations of Dynamic and Crossflow Filtrations 29

1.2.1 Dynamic Filtration 29

1.2.2 Crossflow Filtration 30

2. Review of Industrial Dynamic Filtration Modules 31

2.1 VSEP Vibrating Systems 31

2.2 Multicompartments Systems with Rotating Disks or Rotors between Fixed Membranes 32

2.2.1 The DYNO Filter, BOKELA 32

2.2.2 The Optifilter CR, Metso Paper 33

2.2.3 The FMX System, BKT 33

2.3 Rotating Membrane Systems 33

2.3.1 Rotary Membrane System, SpinTek 33

2.3.2 Single-Shaft Disk Filter (SSDF), Novoflow 34

2.4 Other Developing Dynamic Filtration Modules 36

3. Calculations of Internal Fluid Dynamics in Various Dynamic Filtration Modules 40

3.1 Membrane Shear Rate and Pressure Distribution in Rotating Disk Modules with Fixed Membranes 40

3.2 Membrane Shear Rate in Vibrating Systems 41

3.2.1 Unsteady Membrane Shear Rate in VSEP Modules 41

4. Recent Applications of Dynamic Filtration and Industrial Case Studies 42

4.1 VSEP Applications 42

4.1.1 MF and UF Applications 42

4.1.2 NF and RO Applications 46

4.2 Applications of Rotating Disks and Rotating Membranes Modules 47

4.2.1 MF and UF Applications 47

4.2.2 Applications in NF and RO 52

5. Discussion 54

5.1 Energetic Considerations 54

5.2 Complementarity of Crossflow and Dynamic Filtrations 55

6. Conclusions 56

References 56

Glossary

CFF

   Crossflow filtration

CIP

   Cleaning in place

COD

   Chemical oxygen demand

DF

   Dynamic filtration

MF

   Microfiltration

MSD

   Multishaft disks

NF

   Nanofiltration

RDM

   Rotating disk module

RO

   Reverse osmosis

SBM

   Spinning basket module

TMP

   Transmembrane pressure

UF

   Ultrafiltration

VMBR

   Vibrating membrane bioreactor

VRR

   Volume reduction ratio

Symbols

d

   Vibration amplitude, m

Es

   Specific energy consumed per m3 of permeate, kWh/m3

F

   Vibration frequency, Hz

J

   Permeate flux, 1/L/h/m2

p

   Pressure, bar, Pa

r

   Local radius, m

R

   Disk radius, m

?

   Shear rate, s-1

µ

   Dynamic viscosity, Pas

?

   Kinematic viscosity, m2/s

?

   Density, kg/m3

?

   Angular velocity, rad/s

1. Introduction

The aim of this chapter is to present a relatively recent technique which permits to increase the performance of membrane filtration as compared to classical techniques known as crossflow filtration in which the fluid circulates along a fixed membrane. This new technique, called dynamic filtration, took its origin after 1990 in the United States with the VSEP vibrating system of New Logic in California, the SpinTek module with rotating membranes in Huntington Ca, and the DMF rotating disk system of Pall Corp, Mass. Several German companies Bokela, Novoflow, Novoflow, and Canzler built systems with rotating disks and rotating membranes after 2000.

1.1. Differences between Dynamic and Crossflow Filtration

In crossflow filtration (CFF), the fluid to be treated is circulated by a pump along a flat, a spiral wound, a tubular, or a hollow fibre module and the permeate, containing water and small solutes is collected by filtration across the membrane. This process necessitates applying to the feed a pressure higher than that of permeate, together with a tangential fluid velocity high enough to reduce solute accumulation on the membrane which may cause fouling. But a large tangential velocity will induce a large pressure drop along the membrane, reducing the transmembrane pressure (TMP) in the downstream part of the module and decreasing the average permeate flux.

In dynamic or shear-enhanced filtration (DF), the shear rate at the membrane is created by a moving part such as a disk or a rotor (Lee et al., 1995; Mantari et al., 2006) rotating near fixed membranes or by membranes rotating around a shaft in a housing (Kroner et al., 1988) or by azimuthal vibrations of circular membranes stacked around a vertical axis (VSEP, New Logic, Vane et al., 1999) or by longitudinal vibrations of hollow fibres (Beier et al., 2006).

1.2. Advantages and Limitations of Dynamic and Crossflow Filtrations

1.2.1. Dynamic Filtration

The first advantage is that, by using high rotation speeds and large radius membranes, it is possible to generate very high shear rates at the membrane, up to over 3·105/s (Ding et al., 2002) which can increase the permeate flux by a large factor as compared to CFF, by reducing concentration polarization and membrane fouling. These high shear rates also increase solute transmission through a microfiltration (MF) membrane by reducing cake formation. Since the transfer of small solutes such as ions and molecules through nanofiltration (NF) or reverse osmosis (RO) membranes is mainly diffusive, this transfer is reduced because solute concentration at membranes has been lowered at high shear rates. This leads to a higher rejection rate by the membrane which is the goal of wastewater treatment by NF or RO (Frappart et al., 2006). So an NF membrane in DF may have almost the same rejection as an RO membrane in CFF, but with a higher permeate flux. Moreover, the permeate flux keeps increasing with TMP until higher pressures at high shear rates since the pressure-limited regime is extended, due to decreased concentration polarization.

Another advantage is that the feed flow needs only to be slightly larger than the permeate flow rate in DF since the membrane shear rate is produced independently from the fluid velocity and the power of feed pumps is lower than in CFF. Rotating membranes or disks consume energy at high speeds, but this is offset by the energy gain on pumps, and one has a choice between using high rotation speeds to produce high permeate fluxes or moderate speeds yielding fluxes similar to those in CFF, but with a large reduction in specific energy consumed per unit volume of permeate.

A third advantage is that DF modules can produce retentates with high dry solutes concentrations of at least 70%, since the fluid velocity near the membrane is small, reducing the pressure drop and energy losses due to viscosity. In multicompartment rotating disk modules such as the SpinTek and the Dyno filter, the retentate keeps increasing since compartments are connected in series avoiding the need for recirculating the fluid though the module.

The drawbacks of DF modules are their high cost and complexity, especially when disks rotate between fixed membranes forming separate compartments. Systems such as the KMPT with ceramic membrane disks rotating around parallel shafts inside a housing are simpler to build and to service than those with...