The Effect of Corncob Composition and Torrefaction Temperature on the Calorific Value of Silk Tree Wood Pellets

This study presents the effect of corncob composition with torrefaction process treatment to obtain a calorific value to get the quality of wood pellets. This process was carried out by producing Silk Tree wood pellets using a composition of corn cobs and Silk Tree wood by percentages ratio of 0%: 100%, 25%: 75%, 50%: 50% with temperature variations of the torrefaction process being 225°C, 250°C and 275°C. The pelleting process was carried out using a Richi KL 120 P pelleting machine. The wood pellets were then tested for calorific value using a bomb calorimeter. This study showed that increasing the composition of corn cobs and the torrefaction temperature in the pelleting process will improve the calorific value produced by the pellets. The effect of the percentage of corncob composition on the highest calorific value was obtained at a rate of 50% with a calorific value of 4092 cal/g. Meanwhile, the highest calorific value was obtained in the torrefaction process at a temperature of 275°C with a calorific value of 4160 cal/g, and the lowest calorific value was obtained in the torrefaction process at a temperature of 225°C with a calorific value of 3266.3 cal/g.