INVESTIGATION THE DEPENDENCE OF BULK DENSITY ON THE DISPERSED COMPOSITION OAT FLAKES

Abstract

When oat flakes "Hercules" made at grain factories are used by intermediary enterprises for packaging in consumer packaging, partial crumbling of the product occurs. At the same time, the dispersed composition of the flakes and their bulk density change. The urgency of the problem is due to the need to take into account the bulk density when choosing the size of consumer packaging, as well as when selecting bunker, transporting equipment, feeders and volumetric dispensers for the complete set of production. The subject of the study was mechanical mixtures of whole and partially destroyed oat flakes manufactured in industrial conditions. The purpose of the experimental study is to determine the dependence of the bulk density of oat flakes on their composition. To determine the bulk density, the well-known method of densimetry by free filling was used. Samples of oat flakes "Hercules" from various manufacturers purchased in the Biysk retail chain are analyzed. The average geometric dimensions of solid particles are determined: length 9.2mm, width 5.6 mm, thickness 0.89 mm. The height of the arch of the curved flakes is 1.14 mm. It is assumed that the deformation of the flake arch is caused by the conditions of grain flattening and flake drying. It is again established that the granulometric composition of oat flakes can be represented by three main fractions: 1) large whole or partially splintered flattened particles; 2) medium-sized particles are relatively large fragments of particles – the upper and lower parts of the flattened core; 3) fine crumbs and dust. Content (mass.) these fractions vary – for large particles X from 53 to 94%, medium particles - from 3 to 42%, small particles - up to 5%. The mechanism of formation of medium-sized particles is proposed again – they are formed when the upper and lower parts of the flattened grain are split off during mechanical processing. Physical modeling was carried out - compositions of large and medium particles of variable composition from 0:100 to 100:0 were compiled with a constant content of small particles at the level of 5% and their bulk density was determined. It was found that the bulk density ρ of the tested mechanical mixtures decreases from 448 to 387 kg/m3 with an increase in the content of large particles from 0 to 100 %. It is proposed to approximate the obtained dependence by two straight lines. When the content of a large fraction is up to 70% and above, respectively, the bulk density is determined by the expressions ρ =-0.50 X+447.8 and ρ=-0.85X+471.8, respectively. The obtained dependences can be used in the calculation of equipment for the production and processing of oat flakes - bunkers, conveyors, bulk feeders. It is also possible to apply the data obtained to calculate the size of consumer and transport containers and packaging of oat flakes "Hercules".