Modification and Performance Evaluation of a Biomass Pelleting Machine

The use of biomass as a source of energy has been identified to be energy intensive, involving high handling costs. However, pelletization reduces the bulk density of biomass, thereby reducing the handling costs and enhancing ease of use. This study modified and evaluated an existing hand-operated fish feed pelleting machine. The parts of the machine that were redesigned were the hopper and the power transmission unit. Corncob was used to evaluate the modified machine using the die hole diameter (5, 6 and 7 mm) and the binder quantity (0, 2.5 and 5 wt%) as factors. The average results obtained for machine efficiency, throughput, pellet length and bulk density were 58.83%, 4.24 kg/h, 15.51 mm and 0.160 g/cm3, respectively. The die hole diameter had a significant effect on the pellet length only. The binder quantity had a significant effect on machine efficiency, throughput and pellet length. Machine efficiency and throughput decreased as the quantity of binder increased, and the pellet length increased with the increasing quantity of binder.