ASSESSMENT OF THE PHYSICAL AND MECHANICAL PROPERTIES OF THE PRODUCTS OF CRUSHING SOYBEAN FOR OIL PRODUCTION

Obtaining oil by pressing from soybean involves drying it to a moisture content of 8.0–8.5%. Energy costs can be 3-4 times higher than the costs of evaporation from the free surface of water. Damage to the soybean coat reduces drying time by 1.5 times. The hydraulic resistance to hot air of the grain layer of crushed soybean is greater than that of the whole grain. Reuse of hot air in the grain dryer (recuperation) doubles its path in the soybean layer. The purpose of the article is to determine the hydraulic resistance to hot air in a grain dryer with crushed soybean. It is necessary to calculate the height of the product layer in grain dryers of the type DSP-32 and BRICE-BAKER, to investigate the granulometric composition of crushing products. Crushed soybean with a hammer mill and a roller mill were divided into fractions and weighed using sieves with round holes with diameters of 3.0 and 1.0 mm. The average particle diameter was calculated. The bulk mass of crushing products was determined. In the KOMPAS-3D software package, the height of the product layer was calculated: for grain dryers of the DSP-32 type - 0.25 m, BRICE-BAKER - 0.325 m. The ratio of the area of the outlet windows to the total area of the grain layer of the DSP-32 grain dryer is 0.03917, BRICE-BAKER – 0.021373. The mass share of fractions with a particle size of less than 3 mm in the case of using a roller mill was only 8.5%, which is much less than in the case of using a hammer crusher - 41.4%. Hydraulic resistance to hot air in the grain dryer was calculated in the Mathcad software environment. At the maximum thickness of the layer (0.65 m) and the maximum grain of movement of hot air relative to the total area (0.4 m/s), the hydraulic resistance was 1450 (hammer mill) and 1352 Pa (roller mill). Crushing soybeans increases pressure loss by 2.1 times when using a roller mill and by 2.2 times when using a hammer mill.