Fractal dimensions of coal particles

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Abstract

Since the porous nature of coal is important in its handling, preparation, and utilization, much effort is expended in the measurement of the pore size distribution. Recent work has shown that fractal geometry provides a useful description of porous surfaces by characterizing the pore size distribution over a range of pore sizes by a single number, the fractal dimension D. This paper describes measurements of the pore volume Vp, of a number of coal and char samples by mercury intrusion porosimetry. The fractal dimension was determined from the relation dVpdP ∝ PD−4, where P is the pressure. For the coals, three pressure regimes are indicated by distinct values of D; in order of increasing pressure, these correspond to interparticle penetration, pore penetration, and sample compressibility. The region of pore penetration extends to the highest measured pressures for the chars, which are known to be less compressible. Fractal dimensions for the porous surfaces range from ∼2.6 for some coals to ≲3 for the chars.

References (21)

  • P Pfeifer

    Appl. Surf. Sci.

    (1984)
  • D Avnir et al.

    J. Colloid Interface Sci.

    (1985)
  • C Fairbridge et al.

    Fuel

    (1986)
  • Z Spitzer

    Powder Technol.

    (1981)
  • H Gan et al.

    Fuel

    (1972)
  • Y Toda et al.

    Fuel

    (1972)
  • K.A Debelak et al.

    Fuel

    (1979)
  • C Fairbridge et al.

    Fuel

    (1987)
  • O.P Mahajan et al.
  • B Mandelbrot

    The Fractal Geometry of Nature

    (1982)
There are more references available in the full text version of this article.

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