Design and performance analysis of a coconut coir briquette press machine using an electric motor-driven screw extruder system

Abstrak

Coconut coir waste biomass has strong potential as a renewable energy source through densification into charcoal briquettes. The novelty of this study lies in the development of a small-scale electric motor-driven screw extruder briquetting machine, combined with a comprehensive performance analysis including efficiency, torque, and transmission system, specifically for charcoal material with granular and low-cohesion characteristics. This study aims to design, fabricate, and evaluate the machine performance as well as the quality of the produced charcoal briquettes. An experimental method was employed, including design, manufacturing, assembly, and performance testing of the machine, along with briquette characterization based on SNI standards. The results show that the machine utilizes a 1.5 HP electric motor with a gearbox ratio of 1:35, producing a screw rotation of 40 rpm, a production capacity of 9 kg/h, and an efficiency of 85.24%. The torque at the gearbox output was 267.05 Nm and decreased to 227.6 Nm at the screw, indicating acceptable mechanical energy losses. The produced briquettes exhibited a moisture content of 7.5% and ash content of 7.6% (meeting SNI standards), a calorific value of 4780 cal/g (slightly below the standard), and a burning time of 64.1 minutes. Overall, the developed machine demonstrates effective performance in processing coconut coir charcoal into briquettes, with further improvement potential through optimization of material composition to enhance the calorific value.