No abstract

The aim of this study was to determine the characteristics of fine shredded pan fraction of biomass from sieve analyzer of oscillatory motion and as significance it was comparison the geometric mean particle size calculated according to the S319.4 standard with the arithmetic mean particle size that is assumed as half size of the last sieve 1.65 mm, according to the S424.1 standard. It was found that the finest particles size distributions are less varied between types of biomass (straw, hay and their mix) and are more aligned than particle size distributions for whole mixtures. The particles of hay were more uniform and belonged to ''well sorted'' category than particles of straw and mix, which were non-uniform and belonged to ''moderately well sorted'' category. All biomass particles size belonged to ''very well sorted'' category and particle size distribution were ''very fine skewed'' and ''mesokurtic''. The geometric mean of the finest fraction particle size is almost by half smaller than the value resulting from the half value of the last sieve hole size (1.65 mm) of sieve separator with oscillatory motion in the horizontal plane, as these values are 0.45 and 0.82 mm, respectively. Assuming the 0.1 mm for a pan and the last sieve size of 1.65 mm we suggest to calculate the geometric mean (0.41 mm), which is closer to the experimental value. Application of this recommendation to the standard requires further comparative studies.