Valorization and grouping of wood waste from sawmills in Amazonia for bioenergy

Analyzing the physicochemical and energy properties of industrial wood waste can shed light on important ways to improve and control direct combustion systems. This study aimed to characterize the energy properties of wood waste of 17 tropical species from sawmills in the state of Mato Grosso, Brazil, to obtain groups for energy management of the material. Proximate analysis was performed to determine basic density, ultimate composition, structural chemistry, and heating value. The results revealed minimum basic density of 0.40 g cm^-3 for light wood waste and 0.67 g cm^-3 for moderate wood, reaching a maximum of 0.95 g cm^-3. Most species had a carbon content of over 50% (based on dry mass-db) and a hydrogen content of close to 6% db. The H/C, N/C, and O/C atomic ratios varied between 1.30 and 1.46, 0.0118 and 0.0192, and 0.56 and 0.67, respectively. The average lignin content was greater than 30% db, while the extractives content ranged from 3.3 to 23.6% db. Proximate analysis revealed volatile matter levels greater than 75% db, ash contents less than 2% db, and consistently higher heating values of approximately 20 MJ kg^-1. Principal component analysis revealed distinct groupings of several species, emphasizing the main influences of energy-related properties. We concluded that these wastes have satisfactory properties, emphasizing the importance of grouping species with similar characteristics to optimize the efficiency of combustion systems at various stages.