Production of Biofuel Pellet by Blending Agricultural Residues

Abstract

Agricultural residues have significant potential as feedstock for biomass power plants. However, they have high variation of properties, compositions, and seasonal availability. Blending material becomes a promising strategy for addressing these limitations and improving the energy efficiency of residues. This study examines the properties and characteristics of five biomass materials including rice stubble (RB), rice straw (RW), sugar cane leaves (SL), cassava leaves (CL), and cassava rhizome (CR). Material blending strategy is examined based on seasonal availability in order to produce biomass pellet. RB, RW, and SL are categorized as the primary materials, with the remaining materials serving as supplements. The results show that CL, SL, and CR have the highest Higher Heating Value (HHV) of 19.29, 17.49, and 16.92 MJ/kg, respectively. Meanwhile, RB and RW show lower HHV levels (14.20 MJ/kg and 14.31 MJ/kg, respectively), which are below the heat standard of biomass pellet. To improve the energy property of pellets, the biomass blending techniques were suggested. The two-type blending technique reveals that SL:RW at 80:20 ratio has the maximum heat value of 16.08 MJ/kg. Three-type blending shows that SL:RW:RB in a 60:20:20 ratio has the highest heat value (15.68 MJ/kg). The energy quality of pellet can be increased by blending with the higher HHV materials as supplements, such as CL and CR. For example, the RW:CL (50:50) produced the greatest HHV, 16.25 MJ/kg. The biomass blending approach can provide the solution to the seasonal variation of materials proposed as an alternative use of residues to produce fuels and reduce material shortages and storage costs. Using agricultural wastes has a number of environmental benefits, including reducing harvesting burning, providing a carbon-neutral fuel supply, and promoting the circular economy.