SLS 8: Filter Media
     Part 1: Introduction
     Part 2: Types and Applications
         1. INTRODUCTION: THE FILTER MEDIUM
             1.1 The Function of the Filter Medium
             1.2 The Purposes of Filtration
             1.3 Filtration Mechanisms
             1.4 Range of Filter Media
             1.5 Properties of Filter Media
             1.6 The Structure of Part 2
         2. MACHINE-ORIENTATED PROPERTIES
             2.1 Rigidity/Stiffness/Flexibility
             2.2 Strength
             2.3 Creep/Stretch Resistance
             2.4 Stability of Edges
             2.5 Resistance to Abrasion
             2.6 Stability to Vibration
             2.7 Dimensions of Available Supplies
             2.8 Ability to be Fabricated
             2.9 Sealing/Gasketing Function
         3. APPLICATION-ORIENTATED PROPERTIES
             3.1 Chemical Stability
             3.2 Thermal Stability
             3.3 Biological Stability
             3.4 Dynamic Stability
             3.5 Absorptive Characteristics
             3.6 Adsorptive Characteristics
             3.7 Wettability
             3.8 Health/Safety Hazard Characteristics
             3.9 Electrostatic Characteristics
             3.10 Disposability
             3.11 Suitability for Reuse
         4. FILTRATION SPECIFIC PROPERTIES
             4.1 Filtration Efficiency
                 4.1.1 Definition
                 4.1.2 Filtration mechanisms
                 4.1.3 Pore size
                 4.1.4 Influence of particle characteristics
                 4.1.5 Influence of concentration of suspended solids
                 4.1.6 Influence of pre-treatment
                 4.1.7 Influence of properties of liquid phase
                 4.1.8 Integrity of medium in use
                 4.1.9 Influence of filtration velocity
                 4.1.10 Influence of electrostatic properties of the medium
             4.2 Resistance to Flow
                 4.2.1 Clean medium resistance
                 4.2.2 Used medium resistance
                 4.2.3 Influence of medium on resistance of cake
             4.3 Factors Affecting Cake Cracking
         5. COST FACTORS
             5.1 Typical Costs of Filter Media
             5.2 Influence of Equipment
                 5.2.1 Examples of effect of equipment on initial cost
                 5.2.2 Examples of effect of equipment on annual cost
             5.3 Influence of Operational Factors
                 5.3.1 Influence of flow rate
                 5.3.2 Influence of initial pressure
                 5.3.3 Significance of pressure drop
             5.4 Re-usability
             5.5 The Multilayer Choice
             5.6 Commercial Factors
             5.7 Optimising Filter Media Costs
         6. FILTER MEDIA DEVELOPMENTS AND TRENDS
             6.1 Recent Developments
                 6.1.1 Natural organic materials
                 6.1.2 Polymeric materials
                 6.1.3 Membranes
                 6.1.4 Metals
                 6.1.5 Glass
                 6.1.6 Carbon
                 6.1.7 Ceramics
                 6.1.8 Other media
                 6.1.9 Media usage
             6.2 Future Trends
         7. LOOSE MEDIA
             7.1 Introduction
             7.2 Precoat Media and Filter Aids
                 7.2.1 Diatomite
                 7.2.2 Perlite
                 7.2.3 Cellulose fibres
             7.3 Deep-bed Granular Media
                 7.3.1 Characterisation of granular media
                 7.3.2 Available media
             7.4 Deep Beds with Fibrous Media
         8. SOLID FABRICATIONS
             8.1 Wedge-wire Screens
             8.2 Wire-wound Tubes
             8.3 Stacks of rings
             8.4 Bar Screens
         9. RIGID POROUS MEDIA
             9.1 Ceramics
                 9.1.1 Hard ceramics and stoneware
                 9.1.2 Low density ("soft") ceramics
                 9.1.3 Ceramic membranes
                 9.1.4 Ceramic foams
             9.2 Porous Carbon
             9.3 Porous Plastics
                 9.3.1 Sintered granular plastics
                 9.3.2 Plastic foams
             9.4 Sintered Metals
                 9.4.1 Powder-based media
                 9.4.2 Fibre-based media
                 9.4.3 Woven-wire based media
                 9.4.4 Multilayer media
                 9.4.5 Metal foams
             9.5 Glass Tubes
         10. CARTRIDGES
             10.1 Types of Cartridge
                 10.1.1 Classification by cleanability
                 10.1.2 Classification by element structure
                 10.1.3 Cross-flow membrane modules
             10.2 Sheet Fabrications
             10.3 Yarn-based Cartridges
                 10.3.1 Yarn wound cartridges
                 10.3.2 The Fibrotex cartridge
             10.4 Bonded Media Cartridges
                 10.4.1 Resin-bonded cartridges
                 10.4.2 Thermoplastically bonded cartridges
             10.5 Other Replaceable Elements
             10.6 Filter Bags
             10.7 Lenticular Discs
             10.8 Mechanically-Cleaned Filters
         11. METAL SHEETS
             11.1 Perforated sheets
                 11.1.1 Expanded metal media
                 11.1.2 Electrolytically-formed sheets
                 11.1.3 Laser-cut sheets
             11.2 Woven Wire Mesh
                 11.2.1 Square mesh
                 11.2.2 Zero aperture wire meshes
             11.3 Metal Coated Plastic Mesh
         12. PLASTIC SHEETS
             12.1 Woven Monofilaments
             12.2 Fibrillated Film
             12.3 Porous Sheets
             12.4 Membranes
                 12.4.1 Membrane processes and formats
                 12.4.2 Membrane materials and properties
                 12.4.3 Membrane manufacture
                 12.4.4 Typical membrane materials
         13. WOVEN FABRICS
             13.1 Nature of the Fibre
             13.2 Form of the Yarn
                 13.2.1 Staple yarns
                 13.2.2 Monofilament yarns
                 13.2.3 Multifilament yarns
                 13.2.4 Fibrillated tape yarns
                 13.2.5 Mixed yarns
             13.3 Weave and Finish of Cloth
                 13.3.1 Types of weave
                 13.3.2 Finishing processes
                 13.3.3 Composite fabrics
                 13.3.4 Special-purpose fabrics
                 13.3.5 Knitted fabrics
             13.4 Impact of Variables on Cost of Cloth
             13.5 Properties of Woven Fabric
         14. NON-WOVEN MEDIA
             14.1 Introduction
             14.2 Filter sheets
             14.3 Felts and Needlefelts
                 14.3.1 Needlefelts
                 14.3.2 Surface coatings
                 14.3.3 Typical needlefelt fabrics
                 14.3.4 Electrostatic effects
             14.4 Paper Media
                 14.4.1 Cellulose papers
                 14.4.2 Glass papers
                 14.4.3 Filter papers from other fibres
             14.5 Bonded Media
                 14.5.1 Resin-bonded media
                 14.5.2 Thermally-bonded media
                 14.5.3 Dry-laid spun media
                 14.5.4 Composite non-wovens
         15. REFERENCES
     Part 3: Selection of Filter Media
         1 INTRODUCTION
             1.1 Filtration Purpose
             1.2 Filtration Equipment
             1.3 Filter Media
             1.4 Cost
             1.5 Media Selection
                 1.5.1 General guidance
                 1.5.2 Particle size cutoff
         2 SELECTING LOOSE PARTICLE MEDIA
             2.1 Precoat Media
             2.2 Deep Bed Media
         3 SELECTION OF SOLID FABRICATIONS AS MEDIA
         4 SELECTING RIGID POROUS MEDIA
         5 SELECTING CARTRIDGE MEDIA
         6 SELECTING METAL SHEET MEDIA
         7 SELECTING PLASTIC SHEET MEDIA
         8 SELECTING MEMBRANE MEDIA
         9 SELECTING WOVEN FABRIC MEDIA
         10 SELECTING NON-WOVEN FABRIC MEDIA
             10.1 Wet-laid Media
             10.2 Dry-laid Media
         11 REFERENCES
         12 APPENDIX
     Part 4: Test Procedures
         1. INTRODUCTION
         2. KEY FILTER MEDIA STANDARDS
             2.1 Standards Organisations
             2.2 Existing Standards
         3. TESTING OF MECHANICAL PROPERTIES
             3.1 Rigidity/stiffness
                 3.1.1 General methods
                 3.1.2 Paper
                 3.1.3 Textiles
             3.2 Strength
                 3.2.1 Common criteria of strength
                 3.2.2 Bursting strength
                 3.2.3 Breaking load
                 3.2.4 Extension
             3.3 Resistance to abrasion
         4. THE TESTING OF FILTRATION PROPERTIES
             4.1 Pore size and pore size distribution
                 4.1.1 Bubble point test
                 4.1.2 Mercury intrusion test
             4.2 Porosity
             4.3 Permeability/flow resistance of clean media
                 4.3.1 Air permeability
                 4.3.2 Air resistance
                 4.3.3 Liquid flow
             4.4 Filtration efficiency
                 4.4.1 Clarification
                 4.4.2 Cake filtration
             4.5 Dirt holding capacity
             4.6 Filter integrity
             4.7 Cleanability for re-use
             4.8 Media shedding
             4.9 Extractables in cartridges
             4.10 Determination of medium b factor as guide to blinding
         5. CHARACTERISATION OF MEMBRANES
             5.1 Bubble Point Test
             5.2 Diffusion Testing
             5.3 Mercury Intrusion Method
             5.4 Water Integrity Test
             5.5 Bacterial Challenge Test
             5.6 Latex Sphere Test
             5.7 Gas Adsorption-Desorption
             5.8 Thermoporometry
             5.9 Permporometry
             5.10 Flow Porometry
             5.11 Solute Rejection by Ultrafiltration Membranes
         6. MEDIA TESTING ORGANISATIONS
             6.1 Filtration Equipment and Media Makers
             6.2 Universities and Research Institutes
             6.3 Testing Equipment Suppliers
             6.4 Testing Service Organisations
         7. REFERENCES
     Part 5: Filter Aids
         1. INTRODUCTION
             1.1 Scope of the Report
             1.2 Contents of the Report
             1.3 Glossary of Terms
         2. MECHANISMS AND THEORY
             2.1 Mechanisms of Filtration with Aids
             2.2 Situations where Filter Aids are Used
             2.3 Surface Straining and Depth Filtration
             2.4 Blocking
             2.5 Mechanisms in Depth Filtration
                 2.5.1 Capacity in Depth Filtration
                 2.5.2 Breakthrough
                 2.5.3 Rate of Capture
             2.6 Specific Resistance of Mixed Cakes
             2.7 Properties Required of Filter Aids
         3. AIDS AND THEIR PROPERTIES
             3.1 Diatomite
                 3.1.1 Sources
                 3.1.2 Production
                 3.1.3 Flow Properties
                 3.1.4 Composition
                 3.1.5 Surface Properties
                 3.1.6 Health
                 3.1.7 Supply
             3.2 Perlite
                 3.2.1 Production
                 3.2.2 Sources
                 3.2.3 Structure
                 3.2.4 Flow Properties
                 3.2.5 Composition
                 3.2.6 Surface Properties
                 3.2.7 Supply
                 3.2.8 Health
             3.3 Fibres
                 3.3.1 Asbestos, Production
                 3.3.2 Asbestos, Properties
                 3.3.3 Supply
                 3.3.4 Health
                 3.3.5 Cellulose, Production
                 3.3.6 Cellulose Properties
                 3.3.7 Supply
                 3.3.8 Health
                 3.3.9 Other Fibres
             3.4 Carbon-based Aids
             3.5 Fly Ash
             3.6 Plastics
             3.7 Other Aids
             3.8 Combinations of Aids
                 3.8.1 Mixtures
                 3.8.2 Multi-Layer Precoats
         4. SELECTION AND OPTIMISATION
             4.1 Selection of Type of Aid
             4.2 Grades of Aid Required
                 4.2.1 Precoats on Batch Filters
                 4.2.2 Body Feed
                 4.2.3 Rotary Precoat Filters
             4.3 Quantities Required
                 4.3.1 Precoats for Batch Filters
                 4.3.2 Total Amount of Aid in a Leaf Filter
                 4.3.3 Rotary Precoat Filters
                 4.3.4 Body Feed
             4.4 Test Methods
                 4.4.1 Batch Filtrations
                 4.4.2 Rotary Precoat Filters
             4.5 Handling and Preparation
                 4.5.1 Handling
                 4.5.2 Design of a Feed System
             4.6 Design and Operation of Filters
                 4.6.1 Design Features of Batch Filters
                 4.6.2 Instrumentation
                 4.6.3 Operation of Batch Filters
                 4.6.4 Design Features of Rotary Precoat Filters
                 4.6.5 Operation of Rotary Precoat Filters
                 4.6.6 Requirements of the Medium
             4.7 Reuse of Aids and Recovery of Impurity
                 4.7.1 Thermal Methods
                 4.7.2 Other Methods of Removing One Component
                 4.7.3 Separation Techniques
                 4.7.4 Direct Reuse of Aids
                 4.7.5 Use of Cake Containing Aid and Impurity
             4.8 Cost Data
         5. SUPPLIES OF AIDS
         6. CONCLUDING REMARKS
         7. REFERENCES
         8. NOMENCLATURE

Part 1 Introduction
Part 2 Types and Application
Part 3 Selection
Part 4 Test Procedure
Part 5 Filter Aids

This volume will cover cases where the selection of the medium is separate from selection of the equipment. Thus, screens, strainers, edge filters and cartridge filters are covered in Volume III. Membranes are covered in Volume IV. Volume VIII will cover media for cake filters, filter aids and media for granular media filters It will describe the options and give a systematic procedure for selecting the most suitable media for a particular application. A draft contents list for all 5 parts was presented at the SLS panel meeting in January 1997. The aim is to produce Part 2 (final draft) by 1999/2000.