Advertisement

Phenomenological Study on Fine Particle Misplacement Behavior in Hydrocyclone

  • Chandranath Banerjee
  • Rakesh Kumar Dubey
  • Arun Kumar MajumderEmail author
Technical Paper

Abstract

In spite of widespread applications of hydrocyclone, imprecise particle separation is an inherent limitation associated with it and led to a significant effect on the grinding operation. Such inefficiency is primarily attributable to the misplacement of significant amount of fine particles in the coarser product stream and commonly known as “bypass” in literature. Concerted research efforts are still continuing at various directions to rationalize the occurrence of such phenomenon in a quantifiable manner. This study reveals a fundamental basis towards the genesis and occurrence of bypass in hydrocyclone based on the hydrodynamic of particulate suspension within the turbulent field. Through a series of experiments, we generated carefully controlled experimental data in a 50.8 mm hydrocyclone to analyse the physical response of different parameters (design and operating) on the bypass. Proceeding with the experimental observations we disclose that fines recovery is not equal to that of water split in the underflow. Following this lead, we concluded that the bypass is principally driven by the hydrodynamic condition and the turbulent dispersion of the suspended particle in the prevailing centrifugal force field. Detailed calculations are presented on the basis of solid–fluid two-phase turbulent model to describe the above phenomenological incident. Although our analysis presented here confined to the small diameter hydrocyclone, we are optimistic that the acquired knowledge will be rationale towards the perception of a physical meaning to bypass even for larger classifying cyclones.

Keywords

Hydrocyclone Bypass Hydrodynamics Turbulent dispersions 

List of symbols

dvf

Vortex finder diameter (mm)

dsp

Spigot diameter (mm)

dp

Particle diameter (m)

ρs

Particle density (kg/m3)

ρ

Fluid density (kg/m3)

μ

Fluid viscosity (kg/m3)

Pin

Feed inlet pressure (kPa)

Φs

Solid concentration (%w/w)

sm

Specific gravity of mixture

ur

Particle radial velocity (m/s)

uθ

Tangential velocity (m/s)

ut

Settling velocity (m/s)

\( u^{*} \)

Shear velocity (m/s)

Ldis

Dispersion length scale (m)

Idis

Dispersion index (dimensionless)

G

G force (dimensionless)

ω

Centrifugal acceleration (m/s2)

τp

Particle relation time (s)

mwuf

Mass of pulp water in underflow (kg)

mwf

Mass of pulp water in feed (kg)

U

Mass flow rates of solids in underflow (kg/s)

F

Mass flow rates of solids in feed (kg/s)

ui

Mass fraction of ith size particle in underflow

fi

Mass fraction of ith size particle in feed

S

Selectivity index

C

Classification function

Bp

Bypass fraction

Rf

Volumetric water recovery in underflow (dimensionless)

References

  1. 1.
    Banerjee C, Climent E, and Majumder A K, Chem Eng Sci 152 (2016) 724.CrossRefGoogle Scholar
  2. 2.
    Knowles S R, Woods D R, and Feuerstein I A, Can J Chem Eng 51 (1973) 263.CrossRefGoogle Scholar
  3. 3.
    Hsieh K T, and Rajamani R K, AIChE J 37 (1991) 735.CrossRefGoogle Scholar
  4. 4.
    Fisher M J, and Flack R D, Exp Fluids 32 (2002) 302.CrossRefGoogle Scholar
  5. 5.
    Lim E W C, Chen Y R, Wang C H, and Wu R M, Chem Eng Sci 65 (2010) 6415.CrossRefGoogle Scholar
  6. 6.
    Dyakowski T, and Williams R A, Chem Eng Sci 48 (1993) 1143.CrossRefGoogle Scholar
  7. 7.
    Brennan M, Chem Eng Res Des 84 (2006) 495.CrossRefGoogle Scholar
  8. 8.
    Narasimha M, Brennan M, and Holtham P N, Int J Miner Process 80 (2006) 1.CrossRefGoogle Scholar
  9. 9.
    Wang B, Chu K W, and Yu A B, Ind Eng Chem Res 46 (2007) 4695.CrossRefGoogle Scholar
  10. 10.
    Wang B, and Yu A B, Chem Eng J 135 (2008) 33.CrossRefGoogle Scholar
  11. 11.
    Ghodrat M, Kuang S B, Yu A B, Vince A, Barnett G D, and Barnett P J, Ind Eng Chem Res 52 (2013) 16019.CrossRefGoogle Scholar
  12. 12.
    Banerjee C, Chaudhury K, Majumder A K, and Chakraborty S, Ind Eng Chem Res 54 (2015) 522.CrossRefGoogle Scholar
  13. 13.
    Lynch A J, and Rao T C, in XI International Minerals Processing Congress, Cagliari (1975), p 9.Google Scholar
  14. 14.
    Plitt L R, CIM Bull (1976) 114.Google Scholar
  15. 15.
    Chen W, Zydek N, and Parma F, Chem Eng J 80 (2000) 295.CrossRefGoogle Scholar
  16. 16.
    Coelho M A, and Medronho R, Chem Eng J 84 (2001) 7.CrossRefGoogle Scholar
  17. 17.
    Nageswararao K, Wiseman D, and Napier-Munn T, Miner Eng 17 (2004) 671.CrossRefGoogle Scholar
  18. 18.
    Narasimha M, Mainza A N, Holtham P N, Powell M S, and Brennan M S, Int J Miner Process 133 (2014) 1.CrossRefGoogle Scholar
  19. 19.
    Wills B A, Mineral Processing Technology, Butterworth-Heinemann, Oxford (2006), p 188.Google Scholar
  20. 20.
    Kelsall D F, Trans Inst Chem Eng 30 (1952) 87.Google Scholar
  21. 21.
    Frachon M, and Cilliers J, Chem Eng J 73 (1999) 53.CrossRefGoogle Scholar
  22. 22.
    Neesse T, Dueck J, and Minkov L, Miner Eng 17 (2004) 689.CrossRefGoogle Scholar
  23. 23.
    Schubert H, Int J Miner Process 96 (2010) 14.CrossRefGoogle Scholar
  24. 24.
    Endres E, Dueck J, and Neesse T, Miner Eng 31 (2012) 42.CrossRefGoogle Scholar
  25. 25.
    Dueck J, Adv Powder Technol 24 (2013) 150.CrossRefGoogle Scholar
  26. 26.
    Dueck J, Farghaly M, and Neesse T, Miner Eng 62 (2014) 25.CrossRefGoogle Scholar
  27. 27.
    Nageswararao K, Powder Technol 297 (2016) 106.CrossRefGoogle Scholar
  28. 28.
    Del Villar R, and Finch J A, Miner Eng 5 (1992) 661.CrossRefGoogle Scholar
  29. 29.
    Roldan-Villasana E J, Williams R A, and Dyakowski T, Powder Technol 77 (1993) 243.CrossRefGoogle Scholar
  30. 30.
    Kraipech W, Chen W, Parma F J, and Dyakowski T, Int J Miner Process 66 (2002) 49.CrossRefGoogle Scholar
  31. 31.
    Bradly D, The Hydrocyclones, Pergamon Press, London (1965), p 57.Google Scholar
  32. 32.
    Bourgeois F, and Majumder A K, Powder Technol 237 (2013) 367.CrossRefGoogle Scholar
  33. 33.
    Majumder A K, Yerriswamy P, and Barnwal J P, Miner Eng 16 (2003) 1005.CrossRefGoogle Scholar
  34. 34.
    Kilavuz F S, and Gülsoy Ö Y, Int J Miner Process 98 (2011) 163.CrossRefGoogle Scholar
  35. 35.
    Vallebuona G, Casali A, Ferrara G, Leal O, and Bevilacqua P, Miner Eng 8 (1995) 321.CrossRefGoogle Scholar
  36. 36.
    Braun T, and Bohnet M, Chem Eng Technol 13 (1990) 15.CrossRefGoogle Scholar
  37. 37.
    Dubey R K, Climent E, Banerjee C, and Majumder A K, Int J Miner Process 154 (2016) 41.CrossRefGoogle Scholar
  38. 38.
    Shah H, Majumder A K, and Barnwal J P, Miner Eng 19 (2006) 102.CrossRefGoogle Scholar
  39. 39.
    Banerjee C, Suresh, Majumder A K, and Varma S N, Int J Sci Res 2 (2013) 9.Google Scholar

Copyright information

© The Indian Institute of Metals - IIM 2016

Authors and Affiliations

  • Chandranath Banerjee
    • 1
  • Rakesh Kumar Dubey
    • 1
  • Arun Kumar Majumder
    • 1
    Email author
  1. 1.Department of Mining EngineeringIndian Institute of Technology KharagpurKharagpurIndia

Personalised recommendations