Energy characterization of sawwood generated from mechanical processing of wood in small-scale sawmills

The growing demand for renewable energy sources has stimulated interest in biomass as a sustainable alternative, particularly the use of residues from the wood-processing industry. This study evaluated the energy potential of sawdust from two tropical hardwood species—maçaranduba ( Manilkara spp.) and sucupira ( Bowdichia spp.)—sourced from small-scale sawmills in Camaragibe, Pernambuco, Brazil. The samples underwent analyses for moisture content, bulk density, proximate composition (volatile matter, fixed carbon, and ash), structural chemical composition (extractives, lignin, and holocellulose), and calorific parameters, following standardized protocols (ASTM, NBR, and TAPPI). Beyond reporting conventional fuel properties, the study interprets these results from an application-oriented perspective for decentralized bioenergy use. Both residues exhibited favorable energy characteristics, including high calorific value and high volatile matter content. Maçaranduba showed slightly higher gross calorific value and markedly lower ash content, whereas sucupira presented lower moisture content and, consequently, a 3.5% higher useful heating value. Derived indicators showed that both residues had very similar useful volumetric energy density (approximately 2.4 GJ m −3 ), while sucupira would generate substantially more ash per unit of useful energy than maçaranduba. These results indicate that the two residues are suitable for thermal valorization but are not operationally interchangeable: sucupira is more attractive where lower as-received moisture is advantageous, whereas maçaranduba is more favorable where lower ash generation and reduced ash-management demand are priorities. Thus, the study contributes by translating standard physicochemical characterization into route-selection criteria relevant to small-scale sawmill bioenergy systems.