THE EFFECT OF PARTICLES SIZES ON THE DENSITY AND POROSITY OF THE MATERIAL

The aim of the study was to determine the specific and bulk density and the porosity of the shredded material from Miscanthus according to its particle sizes distribution. The moisture content of the plants was 20%. For the purpose of evaluation of cut particle size distributions a sieve separator was used with a horizontal sieve oscillation and research methodology in accordance with the requirements of ANSI/ASAE S424.1, compatible with the European standard PN-EN 15149-1. It was found that the bulk and specific density and porosity of the shredded material from Miscanthus were depended on its particles size. In the tested range, the Miscanthus particles has a minimal porosity (approx. 90%) and a maximum bulk density (75 kg.m(-3)) at sizes 6 - 8mm. The highest specific density 910 kg.m(-3) was obtained for the finest tested particles (approx. 0,8 mm).