Study of mechanisms of grain dust explosion as affected by particle size and composition.: Part 2. Characterization of particle size and composition of grain dust

Three types of grain dust (corn, wheat, and grain sorghum) and cornstarch (used as a reference) were each divided into varying size fractions (6 to 11) utilizing air and sieve classifications. The particle size distribution and the composition (content of moisture, ash, protein, and starch and fiber) of each size fraction were determined. Dust particles consisting almost entirely of ash material were found to concentrate in specific air-classified size fractions. The total external surface area, the total volume, and the coefficient of variability were calculated from the experimental particle size distribution for each size fraction by utilizing a piecewise log normal approximation. These values were compared with those calculated from the least-squares fitted log normal approximation of the actual distribution.