Study on Fractal Characteristics of Particle Size Distribution Function for Modified-Brown Coal

Particle size distributions (PSDs) are often rendered as cumulative functions, either as number of particles larger than a certain diameter, or as mass smaller than a certain diameter. According to the application status of low rank brown coals of Inner Mongolia, the fractal characteristics of particle size distribution function of raw brown coals and modified-brown coals were analyzed in the paper. The grain size analysis and microstructure analysis of coal samples were measured by the Euro-American gram LS-C (1) type laser Particle analytical instrument, Fourier infrared spectrum (FRIT) and scanning electron microscope (SEM), respectively. The results of the study indicate that raw brown coals and modified-brown coals have fractal feature by using the mathematical model of fractal characteristics of particle size distribution function based on fractal theory. The paper provides the fractal dimensions of modified-brown coals increased with the rank of coal. Thus fractal dimensions can be used as an evaluation index of coal rank providing theoretical basis and distinguish basis for a further study on properties of modified-brown coals.