Characterization and Bioenergy Potential Analysis of Queen Pineapple Waste for Solid Fuel Production via Torrefaction in Camarines Norte, Bicol Region

Global demand for biofuels is predicted to upsurge in the future to unravel the scarcity of fossil fuel source and its environmental impact. Lignocellulosic biomass (LCB), derived from agricultural and industrial wastes, is a promising feedstock for biofuel production because of its advantages such as wide availability, economical, and no issue of food competition. Thus, it provides a significant contribution to meeting the biofuel demand. This study investigates the characteristics and the bioenergy potential of queen pineapple waste (QPW) from the processing facility in Camarines Norte, Philippines, for biofuel production. The physical and chemical characteristics of untreated QPW were determined via proximate and ultimate analyses, respectively. The structure of the QPW (lignin, hemicellulose, and cellulose) was determined through compositional analysis. QP waste was pre-dried at 150 °C for 5 h to lower its moisture content down to ≤ 10%. The pre-dried samples were ground and sifted to reduce the particle size. The torrefaction method was employed to produce biochar in a minimal oxidative atmospheric condition using a muffle furnace with temperature levels and reaction time as variables. Lastly, the bioenergy potential test of raw, pre-dried, and torrefied samples was carried out using a bomb calorimeter. The results revealed that the torrefaction technique increased the higher heating value of raw-dry biomass by 13–68%, depending on the reaction severity.