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adhesion of particles or particles to surfaces

SLIME COATING AND COAGULATION. adhesion of particles or particles to surfaces. Slime coating. AFM-images of slime coatings on mineral surface. M.E. Holuszko et al., Minerals Engineering, 21, 2008, 958-966. Slime coating. Very important phenomenon. Can be useful and harmful.

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adhesion of particles or particles to surfaces

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  1. SLIME COATING AND COAGULATION adhesion of particles or particles to surfaces

  2. Slime coating AFM-images of slime coatings on mineral surface M.E. Holuszko et al., Minerals Engineering, 21, 2008, 958-966

  3. Slime coating Very important phenomenon Can be useful and harmful Ferric oxide slime and flotation of quartz with 10-4 M dodecyl ammonium acetate Chemistry of flotation , M.C. Fuerstenau, J.D. Miller, M.C. Kuhn, AIMM, 1985

  4. Alumina as slime on galena and flotation with xanthate Chemistry of flotation , M.C. Fuerstenau, J.D. Miller, M.C. Kuhn, AIMM, 1985

  5. coagulation homocoagulation heterocoagulation main parameter: stability ratio W

  6. Process delineation (thermodynamics) Gk = Gh – G Gk = Gkd + Gk el + Gk s+ Gk inne That is components: dispersion (d), electrical (el), structural (s), a others

  7. Dispersion interactions H – distance between particles, m R – diameter of particle, m A132 – Hamaker constant, J phase 1 phase 2 phase 3

  8. Dispersion interaction

  9. Dispersion interaction Hamaker constant

  10. Dispersion interaction

  11. Electrostatic interaction 1 – particle electrostatic potential, V, 2 – the other particle electrostatic potential, V, R1–particle radius, m, R2 – the other particle radius, m,  – dielectric constant (usually water) 0 – dielectric permeability in vacuum, 8,854187817·10–12 C2 N–1 m–2 1/ – Debye radius (thickness of ewp), m, H – distance between interacting objects, m.

  12. Electrostatic interaction

  13. Structural interaction For flat particles For spherical particles K , K* , Eso- constants l - parameter correlating standing for thickness of oriented water molecules at the surface of particle H - distance between particles R - radius of particles

  14. Total interaction

  15. Total interaction

  16. Stability ratio W

  17. Time of half-life t1/2 of hypothetical emulsion containing 1 m droplet and having energy barrier Vmax one radius apart from the droplet surface (after Friberg, 1991)

  18. Main parameter: stability ratioW

  19. selective coagulation

  20. selective coagulation

  21. selective coagulation

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