BSH 12: Particle Segregation
     Part 1: User Guide to Segregation
         1. Introduction
         2. The Importance of Segregation
             2.1 Prevalence
             2.2 Propensity of a Material to Segregate
             2.3 Circumstances under which Segregation occurs
             2.4 Intensity of Segregation
             2.5 Magnitude of Segregation
             2.6 Consequences of Segregation
                 2.6.1 Typical Features affecting Product Quality, Value or Fitness for Use
                 2.6.2 Typical Operating Problems that arise due to Segregation
             2.7 The Significance of Segregation
                 2.7.1 Product
                 2.7.2 Process
                 2.7.3 Production
                 2.7.4 Personnel
                 2.7.5 Plant
                 2.7.6 Health and Safety
             2.8 Quantification of Segregation
         3. Particle Properties Influencing Segregation Propensity and Ability
         4. Bulk Variables Influencing Segregation
             4.1 Powder State and Dynamic Situation
             4.2 Second Phase Effects
             4.3 Fluid Phase and Three Phase Effects
         5. Force Origins That Give Rise to Segregating Mechanisms
             5.1 Gravity
             5.2 Particle-to-Particle Contact
             5.3 Contact Friction
             5.4 Impact
             5.5 Density Differentials
             5.6 Wedging
             5.7 Bouncing
             5.8 Rolling
             5.9 Fluid Drag
             5.10 Static Electricity
         6. Processes That Segregate Particles
             6.1 'Sifting' and 'Percolation'
             6.2 Angle of Repose Differences
             6.3 'Floating' and 'Sinking'
             6.4 'Up Thrusting' - A Variation of Wedging
             6.5 Dynamic Particle Behaviour
             6.6 Elutriation, Transverse and Countercurrent Gas Flow
             6.7 'Capture'
             6.8 Attrition Processes
             6.9 Impact Fluidisation
                 6.9.1 Fluidised Bed Condition
                 6.9.2 'Over-Saturated' Bed
             6.10 Rotating Bed Processes
             6.11 Lateral Diffusion / Fines Barrier Effect
             6.12 Vibrated Beds
         7. Regimes in Which Segregation Processes Occur
             7.1 'Free Fall' and Trajectory Streams
             7.2 Repose Flow Stream
             7.3 Static and Dynamic Beds
             7.4 Shearing Planes
             7.5 Impact on Contact Surface
             7.6 Counter Gas Flow
             7.7 Impact Stream onto Bed
             7.8 Fluidisation
             7.9 Avalanching
         8. Operations Which Give Rise to Segregation Processes
             8.1 Storage
             8.2 Patterns of Flow in Silos
                 8.2.1 Basic Flow Patterns
                 8.2.2 'Mass Flow' Silos
                 8.2.3 General Flow Patterns in Silos
                 8.2.4 Patterns of Outflow
                 8.2.5 Special Cases of Flow Regimes
             8.3 Handling
                 8.3.1 Filling of Containers
                 8.3.2 Emptying of Containers
                 8.3.3 Confined Flow Streams
                 8.3.4 Mechanical Devices
             8.4 Conveyors
             8.5 Fluidisation
             8.6 Pneumatic Conveyors
         9. Operational Variables
             9.1 Scale
             9.2 Process Rate
             9.3 Equipment Form
             9.4 Production Sequence
             9.5 Extended Batch Delivery Systems
             9.6 Residue
             9.7 Changes of Use
             9.8 Plant Management
         10. Process Variables
             10.1 Temperature
             10.2 Pressure
             10.3 Flow Rates
             10.4 Time
         11. Ambient Conditions and Ambient Variables
             11.1 Void Gas
             11.2 Vapours and Gas Mixtures Other than Air
             11.3 Temperature
             11.4 Humidity
             11.5 Moisture
             11.6 Pressure
             11.7 Vibration
             11.8 Time Effects
         12. Measurement of Segregation
             12.1 Purpose
             12.2 Scale of Scrutiny
             12.3 Number or Frequency of Samples
             12.4 Significance of Sample Location
             12.5 Single or Multiple Aspects
             12.6 Form and Degree of Variation
             12.7 Mono or Multi-Component
             12.8 Sampling Techniques
             12.9 Measuring Methods
             12.10 Analysis of the Results
             12.11 Coefficients of Variations
             12.12 Modelling of Segregation
         13. Testing
             13.1 Sample Selection
             13.2 Sample Procurement
             13.3 Sample Preparation
             13.4 Sample Analysis
             13.5 Criteria of Acceptance
             13.6 Reference Standards
         14. Controlling Segregation
             14.1 Problem Identification and Evaluation
             14.2 Minimising the Predisposition of a Material to Segregate
                 14.2.1 Particle Modifications
                 14.2.2 Reduce the Particle Size Difference
                 14.2.3 Extraction of Fines
                 14.2.4 Adjust Ratio of Fines to Coarse
                 14.2.5 Modify Shape, Texture or Surface Condition to Make More Cohesive
                 14.2.6 Add Moisture or a Weak Binding Agent
                 14.2.7 Alter Ambient Conditions
                 14.2.8 Reduce Particle Attrition During Handling
             14.3 Minimising the Tendency for Segregation to Occur
                 14.3.1 Change the Operating Procedure (with Existing Equipment)
                 14.3.2 Alter Flow Rates
                 14.3.3 Change the Batch Size(s)
                 14.3.4 Alter the Operation Sequence
                 14.3.5 Hopper Management Planning
                 14.3.6 Reduce Segregating Opportunities (Modify Equipment)
                 14.3.7 Change the Bulk Flow Pattern
                 14.3.8 Re-Arrange Equipment Form or Layout
                 14.3.9 Use Alternative Handling Method
                 14.3.10 Consider Continuous versus Batch Handling or Process
                 14.3.11 Condition the Powder by Different Handling
                 14.3.12 Defer Mixing, Hence Potential to Segregate, to Late Stage of Production
                 14.3.13 Avoid or Minimise Segregating Stimulants
                 14.3.14 Alter Trajectory Streams
                 14.3.15 De-Aerate Rapidly to Reduce Bed Penetration
                 14.3.16 Disperse Fill to Avoid Repose Stream Sifting
                 14.3.17 Reduce Impact Fluidisation
             14.4 Redressing Segregation Which Has Taken Place
                 14.4.1 Address Non-Mass Flow Hopper Usage and Design
                 14.4.2 Use of a Mass Flow Hopper
                 14.4.3 Redress Segregation in a Mass Flow Hopper
                 14.4.4 The Use of Inserts
                 14.4.5 Exploit Selective Extraction Techniques
                 14.4.6 Restore Chute Segregation
                 14.4.7 Take Advantage of Feeder Extraction Patterns
         15. Summary
         16. Bibliography
         17. Acknowledgements

Volume BSH 12: Four Summary Research Reports on Screw Conveying Testwork on Wet Bulk Solids.