Abstract
This work leads to improvement towards fuel efficiency of biomass by pelletizing at different pressures with different percentage of coal. Two species of wood sawdust–Gurjan Balsam, Teak, and a coal sample were used in this study. Analysis of unprocessed raw materials were conducted to evaluate their fuel characteristics. From our observation, it is eminent that pellet density increases radically at pressures of 3.055–6.111MPa. This phenomenon eventually causes minor density increases with increased pressure. An increasing pattern was also observed in the variation of the heating value of pellets with the increased pelletizing pressure in both samples. Bonding between biomass particles has been identified as the main factor which influences the heating value. Consequently, this variation in bonding alters the heating value at different pressures. The formation of the solid bridge due to lignin flow and inter-diffusion between adjacent biomass particles are responsible for binding with coal and increased heating value at higher pressures. The presence of van der Waals forces and hydrogen bonding also increases the heating value with increasing pressure.