Sustainable Agricultural Waste Shredder and Bio-Pellet Production System

Abstract

This study highlights the development of an environmentally friendly agricultural waste shredder and pellet-making machine. The primary function of this machine is to chop agricultural residues such as coconut and areca leaves which can then be utilized for vermicomposting. The concept was devised by analyzing four distinct machines and their operational mechanisms. The design integrates safety considerations for users in both working conditions and maintenance. Keeping in mind user requirements and affordability, a prototype was constructed. The key components of this equipment include a single-phase motor, bearings, a structural frame, cutters, and a shaft. The frame is constructed using mild steel, while stainless steel is employed for fabricating the cutter tips. Two cutters are mounted on the shaft, and power from the electric motor is transmitted via a belt drive assembly. The chopping action within the machine occurs due to a combination of tensile, friction, and impact forces. The processed waste is ultimately collected at the bottom in pellet form. Upon passing a single-phase AC, the motor is activated. This 1 HP, 1440 rpm motor is connected to a 4-inch pulley, while the cutter shaft, fitted with blades, is attached to a 2-inch pulley. As a result, the shaft speed doubles to 2880 rpm. The machine operates purely on rotational force, eliminating the need for a gearbox. At high speeds, the blades rotate with the shaft, exerting a hammering effect on the inserted materials. The gap between the sizer and blade is limited to half an inch. When the blades spin rapidly, centrifugal force is generated, which lifts uncut pieces and repeatedly strikes them until they pass through the sizer holes.