DETERMINATION OF THE IMPACT OF CLOSED-TYPE IMPELLER DESIGN ON THE EFFICIENCY OF INDUSTRIAL HEMP SEED SHELLING

Abstract

The article presents the results of a study on the efficiency of the centrifugal dehulling method for industrial hemp seeds using a device equipped with a closed-sector impeller with four profiled radial channels.
At an impeller rotational speed of 6000±200 rpm, the kernel yield in the first three cycles was 9.27%, 12.75%, and 7.86%, respectively, whereas the fourth and fifth cycles produced only 3.54% and 1.39%. The decrease in yield at later stages is explained by the increased strength of the seed hulls remaining after the previous cycles. The share of unhulled seeds gradually decreased from 71.24% after the first cycle to 1.90% after the fifth.
The results indicate that limiting the number of dehulling cycles to three is advisable, as it significantly reduces operating costs without reducing kernel yield. The geometry of the radial channels (20×20 mm, 44 mm long), combined with a rotational speed of 6000 rpm, provided sufficient centrifugal acceleration for effective dehulling. Within the tested design, the configuration with four channels was recognized as a technically justified solution for the basic setup.