Evaluating the Influence of Carbonization on the Essential Properties of Sawdust

Abstract

This study evaluates the influence of carbonization on the essential physicochemical properties of sawdust to determine its suitability for bioenergy and material applications. Raw sawdust and its carbonized derivative (biochar), produced via pyrolysis at 600 °C for 5 hours, were analyzed for density, moisture content, volatile matter, ash content, particle size, water absorption capacity, uniformity index, and heat energy. Results show that carbonization significantly altered several key properties. Density decreased from an average of 154.16 kg/m³ to 112.02 kg/m³, while moisture content dropped from 12.41% to 7.31%, enhancing storage and combustion stability. Conversely, volatile matter, which was initially low in sawdust (mean: 3.93%), increased markedly to 37.79% in biochar, indicating higher reactivity. Ash content rose from 2.87% to 17.61%, reflecting the concentration of inorganic residues post-carbonization. Particle size was slightly reduced (from 0.3457 mm to 0.3317 mm), although this change was not statistically significant (p > .05). A major shift was observed in water absorption capacity, which almost doubled from 336.08% to 619.40%, indicating enhanced porosity due to pyrolysis. The heat energy content also increased significantly from 16.56 MJ/kg to 24.96 MJ/kg, confirming improved energy potential. The uniformity index remained medium across all samples, showing consistency in particle grading. Overall, carbonization positively influenced fuel properties such as energy content and moisture resistance, although trade-offs in ash content and density may limit applications requiring compactness or low residue. These findings support the tailored use of carbonized sawdust in energy generation and material enhancement depending on end-use requirements.