Characterization and quality analysis of biomass pellets prepared from furfural residue, sawdust, corn stalk and sewage sludge.

Searching and exploring for new biomass sources is essential for biofuels production. Furfural residue pellets (FRPs), sawdust pellets (SPs), corn stalk pellets (CSPs) and sewage sludge pellets (SSPs) were produced using single pellets press, their quality was analysed and compared. Proximate and ultimate parameters varied for all pellets depending on their chemical composition. FRPs had the highest relaxed density (1.431 g/cm3) than SPs and CSPs at 130 °C and strength (∼6 MPa) than CSPs and SSPs at 200 °C. Among all pellets, SPs achie v ed higher strength of 10.38 MPa. Porosity (3.42 v%) and moisture absorption (7.68%) of FRPs were found lower than SPs, CSPs, and SSPs. Compression energy for FRPs (24.15 J/g) and SSPs (18.64 J/g) was found to be lower than SPs and CSPs, making more economic sense and indicating the potential of biomass wastes for co-pelletization with other biomass sources. Higher heating value of FRPs (22.45 MJ/kg), SPs and CSPs (∼20 MJ/kg) were found satisfactory and met the set standards. FRPs had higher volumetric energy density (32.06 kJ/cm3) compared to other pellets. There were no or very less heavy metals contents in FRPs, SPs and CSPs than SSPs. From overall ranking, FRPs were found higher in rank, followed by SPs. • Physical, chemical, mechanical and thermal characteristics of pellets were studied. • Among all, FRPs had lower porosity, moisture absorption and higher strength at 130 °C. • SPs achieved higher relaxed density and strength and lower porosity and E c at 200 °C. • HHV of FRPs (22.45 MJ/kg), SPs and CSPs (∼ 20 MJ/kg) met the Enplus standards. • From overall ranking, FRPs were found higher in rank, followed by SPs. [ABSTRACT FROM AUTHOR]