Research on the optimal design and process parameters of a castor seed cleaning machine

Inthe context ofthe modern EU bioeconomy, the use ofindustrial crops, particularly castor beans (Ricinus communisL.), isrelevant for the production ofindustrial and energy products without competing with food crops. Castor oil isused for the production ofbiodiesel, lubricants, paints and coatings, cosmetics, and pharmaceuticals. InUkraine, castor beans can becultivated onlow-yield soils, with seed yields ranging from 1.5t/ha to2.1 t/ha depending onthe variety. However, the morphological features ofthe fruits and uneven ripening complicate the mechanisation ofharvesting and seed cleaning processes. Existing equipment designed for other crops cannot beapplied due tothe risk ofdamaging the castor seeds. Adesign ofacastor seed cleaning machine has been proposed, combining mechanical fruit shelling with the aerodynamic separation ofthe mixture. The machine isequipped with aneccentric crushing cone, rubber linings, apneumatic separation channel, acyclone, and anautomated control unit. Asaresult ofnumerical modelling and experimental studies ofthe process ofseparating and cleaning castor seeds, dependencies were obtained for the productivity ofthe developed machine Q, power consumption P, specific energy consumption E, fraction ofunshelled fruits (segments) ξf, content ofthe clean seed inthe seed collector ψs-s depending onthe distance between the reverse and crushing cones δ, rotation frequency ofthe crushing cone n, diameter ofthe feed opening Din, inclination angle ofthe crushing cone axis γ, and airflow velocity V. Amulti-criteria optimisation method was applied tofind the optimal operating modes: δ=10.8mm; n=282 rpm; V=3.6m/s; Din=98mm; γ=3.6; β=20.3. The following results were achieved: E=0.0394MJ/kg; Q=163.4kg/h; P=1861W; ξf=0.099; ψs-s=0.958. The obtained results confirm the efficiency of the proposed design for industrial implementation.