Improving the operation of a drum grain dryer with justification of the low-temperature mode parameters

Abstract

The proposed engineering and tech-nological solutions are aimed at improv-ing the operation of a low-temperature drum grain dryer by using a combined mechanical vibration exciter, with the further justification of low-temperature regime parameters. Existing vibration technologies imply the high-temperature drying of food grains with further utili-zation of spent heat carrier for reheat-ing it. In this case, the high-temperature drying of cereals and seed crops (grains, onions, etc.) does not make it possible to maintain high germination, emphasizing the need for low-temperature treatment, which, in this case, reduces the efficien-cy of spent heat carrier. Therefore, to improve the efficiency of the drying pro-cess and technology, it has been pro-posed to employ vibration low-frequen-cy technologies that ensure seed quality.The trajectory and the kinetic ener-gy of the drum container with a com-bined mechanical vibration exciter have been calculated for the improved vibratory drum grain dryer. The ratio-nal vibration intensity for seed dry-ing providing the following kinetic characteristics has been established: vibration speed, to 0.03 m/s; vibration acceleration, 30 m/s2; vibration inten-sity, 2.6 m2/s2; at amplitude vibration not exceeding 2 mm. It has been also established that the intense warming of a barley layer occurs at a tempera-ture of 50 °C and a humidity of 13.5 %, the final temperature is 42.4 °C, and, at 40 °C, is, accordingly, 35.4 °C. This has confirmed that the low-tempera-ture drying of barley seeds of the vari-ety “Stalker” (Ukraine) takes place during the periods of constant and falling drying speed characterized by a high level of germination (95...93 %).