The Hydrocyclone

Preface


1. Introduction


2. Historical Development


3. Mode of Operation


3.1. The Flow Pattern


3.2. Velocity Distributions


4. Tangential Velocity


4.1. Alternative Velocity Distribution Relationships


4.2. Experimental Measurement of Tangential Velocity Distributions


4.3. Values for The Flow Pattern Constants, n, α and ß


4.4. Summary of Data on n, α and ß and The Effects of Their Values on Design and Operating Variables


5. Areas of Application and Operational Characteristics


5.1. Separation of Solids from Liquid


5.2. Separation of Solid from Solid


5.3. Separation of Liquid from Liquid


5.4. Separation of Gas from Liquid


5.5. Miscellaneous Applications of the Hydrocyclone


5.6 Operational Features of the Hydrocyclone


6. Performance of Hydrocyclones


6.1. The Efficiency of a Cyclone


6.2. Pressure Drop in a Cyclone


6.3. Volume Split or Flow Ratio


7. Design Variables


7.1. Cyclone Diameter


7.2. Aperture Diameters


7.3. Vortex Finder Dimensions


7.4. Body Dimensions


7.5. Feed Inlet Geometry


7.6. Interior Surface Finish


7.7. Materials of Construction


7.8. Overflow and Underflow Collection Arrangements


7.9. Manifolding of Feed Lines


7.10. Summary of Design Variables


8. Operating Variables and Control of Operation


8.1. Feed Flow Rate


8.2. Feed Pressure or Pressure Drop


8.3. Solids Concentration in Feed and Underflow


8.4. Solids Size and Shape


8.5. Solids Density and Liquid Medium Density


8.6. Liquid Medium Viscosity


8.7. Reynolds Number in Cyclones


8.8. Back Pressure


8.9. Volume Split


8.10. Control of Cyclone Operation


9. Categories of Cyclone


9.1. The Cyclone Thickener


9.2. The Cyclone Classifier


9.3. The Cyclone Washer


9.4. Cyclone Liquid Separator


9.5. Mass Transfer Cyclone


9.6. Cyclone Gas Separator


9.7. Miscellaneous Cyclone Duties


10. Commercial Cyclones


11. Fields of Application in Industry


11.1. The Pulp and Paper Industry


11.2. Coal Preparation


11.3. Applications in Mineral Dressing


11.4. Applications in the China Clay Industry


11.5. Applications in the Cement Industry


11.6. Applications in the Whiting Industry


11.7. Applications in the Phosphate Mining Industry


11.8. Applications in the Sand and Gravel Industry


11.9. Applications in the Food Industry


11.10. Applications in the Petroleum Industry


11.11. Applications in the Chemical Industry


11.12. Applications in the Nuclear Power Industry


11.13. Applications in the Iron and Steel Industry


12. Equipment of the Cyclone Type


13. Bibliography


14. Patent Review

Appendix

Author Index

Subject Index

Other Titles in the Series

List of Illustrations

Fig. 1. Principal Features of a Hydrocyclone

Fig. 2. Schematic Representation of the Spiral Flow

Fig. 3. Schematic Representation of the Locus of Zero Vertical Velocity and the Air Core

Fig. 4. Schematic Representation of the Short Circuit and Eddy Flows

Fig. 5. (a) Dye Photograph of Outer Downward Movement

Fig. 5. (b) Dye Photograph of Inner Reversal

Fig. 5. (c) Dye Photograph of "Mantle"

Fig. 5. (d) Dye Photograph of "Mantle" Obtained by Direct Injection

Fig. 5. (e) Dye Photograph of Short Circuit Flow

Fig. 5. (f) Dye Photograph of Multiple Eddys

Fig. 6. (a) Photograph of Unestablished Vortex—With Overflow

Fig. 6. (b) Photograph of Established Vortex—Low Rate

Fig. 6. (c) Photograph of Established Vortex—High Rate

Fig. 7. Vertical Velocity Distribution

Fig. 8. Locus of Zero Vertical Velocity Extended into the Cylindrical Section

Fig. 9. Radial Velocity Distribution

Fig. 10. Tangential Velocity Distributions Corresponding to Given Relationships

Fig. 11. Tangential Velocity Distribution

Fig. 12. (a) Photograph of Spiral of Dye within the Region of Constant Angular Velocity

Fig. 12. (b) Photograph of Dye Remaining Outside the Region of Constant Angular Velocity

Fig. 13. Relationship Between α and β

Fig. 14. Theoretical Tangential Velocity Distribution

Fig. 15. Theoretical Tangential Velocity Distribution. Data of Fig. 14 Plotted Logarithmically

Fig. 16. Element of Fluid in a Rotating Body

Fig. 17 Relationship between β and Ac/Ai

Fig. 18. Data of Fig. 17 Given in β Form and Compared with Yoshioka and Hotta Relationship

Fig. 19. Comparison of Yoshioka and Hotta Equation for β with Data of Table 1

Fig. 20. Arrangement for the Series Connection of Cyclones

Fig. 21. Typical Efficiency Curves

Fig. 22. Two-Stage Liquid-Liquid Separation

Fig. 23. Capital Cost of Cyclones

Fig. 24. Shear Rate as a Function of Cyclone Radius

Fig. 25. Maximum Rate of Shear versus Cyclone Size

Fig. 26. Shear Diagrams and Apparent Viscosities of Clay Suspensions

Fig. 27. Calculated Values for Centrifugal Acceleration as a Function of Cyclone Radius

Fig. 28. Reduced Efficiency Curve of Yoshioka and Hotta

Fig. 29. Data Showing the Applicability of the Intermediate Law of Settling in Small Diameter Cyclones

Fig. 30. Particle Equilibria in Relation to the Locus of Zero Vertical Velocity

Fig. 31. Experimental Data on Cy50

Fig. 32. Comparison of Calculated Reduced Efficiency Curve with Curves Obtained in Practice

Fig. 33. Values for Correlation Parameter ζ of de Gelder

Fig. 34. Plot of versus (From de Gelder)

Fig. 35. Values for Correlation Parameter J of de Gelder

Fig. 36. Constants for Use in Rietemas' Pressure Drop Correlation

Fig. 37. Pressure Drop versus Flow Rate

Fig. 38. Rate of Injection of Momentum versus Inlet Diameter

Fig. 39. Change in Vortex Finder Length

Fig. 40. The Effect of Change in Vortex Finder Length on the Efficiency of Separation of Different Size Groups

Fig. 41. Pressure Drop versus Capacity for Cyclones of Different Length and Cone Angle

Fig. 42. Types of Feed Inlet in Use

Fig. 43. Pressure Drop versus Capacity for Different Feed Levels

Fig. 44. Effect of Insertion of a Probe on Pressure Drop

Fig. 45. Stroboscope Photograph of Oversize Particles Retained on the Cyclone Wall

Fig. 46. Diagram of a Cyclone Overflow Header

Fig. 47. Photographs of Underflow Pot Operation

Fig. 47. (a) Low Flow Rate

Fig. 47. (b) High Flow Rate

Fig. 48. Effect of an Underflow Pot on Separation Efficiency

Fig. 48. (a) Low Flow Rate

Fig. 48. (b) High Flow Rate

Fig. 49. Flow Ratio, Rf, as a Function of Feed Concentration

Fig. 50. Effect of Feed Concentration on Total Flow Rate

Fig. 51. Effect of Feed Concentration on Total Flow Rate, Comparing Two Suspensions

Fig. 52. The Effect of Reynolds Number on the Relative Motion of Differently Shaped Particles

Fig. 53. The Effect of Viscosity on the Pressure Drop Relationship

Fig. 54. The Effect of Viscosity on Flow Rate at Constant Pressure Drop

Fig. 55. Effect of Viscosity on Volume Split and Flow Ratio

Fig. 56. Effect of Reynolds Number on Pressure Loss Coefficient

Fig. 57. Evidence for Controlling Influence of Reynolds Number on Separation Efficiency

Fig. 58. Evaluation of the Optimum Reynolds Number

Fig. 59. Effect of Underflow Proportion on Separation at Constant Pressure Drop

Fig. 60. Effect of Underflow Proportion on Separation at Constant Reynolds Number

Fig. 61. Types of Underflow Valve

Fig. 62. Types of Underflow Control

Fig. 63. Pump Suction Control for Controlling Cyclone Performance

Fig. 64. Cyclone Modifications to Improve Classification Performance

Fig. 65. Methods of Expressing Performance and Efficiency of Sink-Float Separators

Fig. 66. Effect of Du/D0 Ratio on Density of Separation

Fig. 67. Effect of Inlet Pressure on Sink-Float Separation

Fig. 68. Graphical Correlation of Sink-Float Data

Fig. 69. Per Cent Solids to Overflow or Underflow as a Function of Density Difference, Particle Size, and Volume Split

Fig. 70. Calculated Separation Curves for a 6 in Cyclone Washer

Fig. 71. Cyclones for Liquid-Liquid Separation

Fig. 72. Diagram Showing The Principle of a Super-Centrifuge Separator Bowl Top

Fig. 73. Hydrostatically Balanced Liquid-Liquid Cyclone

Fig. 74. Variation in Separation Efficiency with Volume Split

Fig. 75. Variation in Composition of Overflow and Underflow with Volume Split

Fig. 76. Variation in Separation Efficiency with Feed Rate

Fig. 77. Effect of Premixing on Phase Separation

Fig. 78. Example of Equilibrium and Operating Lines for Solvent Extraction

Fig. 79. Mass Transfer Efficiencies and Phase Separation Efficiencies versus Feed Rate

Fig. 80. Mass Transfer Efficiency versus Phase Separation

Fig. 81. Types of Cyclonic Gas Liquid Separator

Fig. 82. Cyclonic Gas Separators in the Pulp and Paper Industry

Fig. 83. The Clust-R-Clone, Six 8 in Units

Fig. 84. Dorr TM Cyclones

Fig. 85. Dorr TM3 Cyclone Unit

Fig. 86. Dorr TMC-60 Cyclone Unit

Fig. 87. Photograph of Dorr P50 Porcelain Cyclones

Fig. 88. Cross Sectional Drawing of a Dorr 6 in FR Cyclone

Fig. 89. Glass "Laboratory Set" Cyclone of Liquid-Solid Separations Limited

Fig. 90. Components of Liquid-Solid Separations Limited Cyclone

Fig. 91. Two-Stage Krebs Cyclone

Fig. 92. Capacity Ranges of Sharpies "HC" Cyclones

Fig. 93. Capacity Ranges of Sharpies "HE" Cyclones

Fig. 94. Daynor Decanter

Fig. 95. An "Ideal" Three-Stage Pulp Cleaning System

Fig. 96. Practical Example of Cyclone Coupling in Pulp Cleaning

Fig. 97. Performance Data for 3 in and 6 in Cyclones on Pulp Cleaning

Fig. 98. Fiber Loss as a Function of Inlet Concentration

Fig. 99. The "Coretrap"

Fig. 100. The "Hy-Kleener" Vortex Finder Shroud

Fig. 101. Cross Sectional Drawing of the "Radiclone"

Fig. 102. Original Flow Sheet of a Cyclone Washery

Fig. 103. Flow Sheet of a Cyclone Washing Plant Using Water Only

Fig. 104. Flow Sheet for The Closed Circuit Grinding of Copper Flotation Feed

Fig. 105. Corn Starch Process Flow Sheet

Fig. 106. Degritting of Mill Starch

Fig. 107. Potato Starch Process Flow Sheet

Fig. 108. Cyclone Battery for Corn Starch Processing

Fig. 109. Savings in Load Time in Cyclic Centrifugal Filters by Preconcentration of the Feed

Fig. 110. Fixed Impellor Cyclone of Sineath and Delia-Valle

Fig. 111. Blade Angle and Throat Area Defined

Fig. 112. Comparison of Efficiency Curves for Cyclone and Fixed Impellor Cyclone

Fig. 113. Cut-Away View of the "Centriclone"

Fig. 114. Photograph of Voith High Consistency Purifier

Fig. 115. Schematic Drawing of the Statifuge

Fig. 116. Photograph of the Statifuge

Fig. 117. Theoretical Performance Area for the Statifuge

Fig. 118. Performance Comparison Between The Statifuge and Cyclone

Fig. 119. The Tedman Separator

Fig. 120. Cross Section of the Turpinson Separator

Fig. 121. Cut-Away Model of the Turpinson Separator

Plates I-X