A Prototype of Simultaneous Husking and Separating Machine for Dry Betel Nut

After harvesting and drying, areca nut (betel nut) processing requires shell cracking and separation of the kernel from the shell. Conventional processing often relies on manual sorting or additional separation machines after husking. To address this limitation, this study developed a mechanically simple machine that integrates husking and separation of full nuts, broken nuts, and shells into a single processing unit without cutting blades or complex control systems. The proposed machine employs all-terrain vehicle (ATV) tires as husking elements, providing a compliant and high-friction contact surface to promote shear-dominant shell detachment in combination with concave metal sieves. Dried areca nuts are fed through a hopper into the shearing zone formed between the rotating ATV tires and stationary concave sieves, where shells are detached through compressive and tangential forces. The husked material is then conveyed to an integrated separating system for in-line classification. Experimental results showed that, under selected operating conditions (tire pressure of 138 kPa, wheel-sieve clearance of 20 mm, husking wheel speed of 442 rpm, and separating system speed of 337 rpm), the machine achieved 80.2% fully husked nuts, 13.8% unhusked nuts, and 6.0% broken nuts. The results demonstrate the feasibility of a shear-based, integrated husking-and-separating approach for dried areca nut processing.