Pretreatment of pine and poplar particleboards with Pleurotus ostreatus (Jacq.): physicomechanical and chemical properties of wood, potential of solid fuel and biogas production

This study, which evaluated the effects of biological pretreatment on comminuted pine and poplar shavings and particleboards with urea–formaldehyde resin (UF), utilising Pleurotus ostreatus (P. ostreatus), holds statistically significant implications for the future of waste management and biogas production. The 17-week fungal pretreatment was followed by a physicomechanical and chemical analysis of raw and pretreated materials and pressure agglomeration to produce pastilles and an anaerobic digestion process to produce biogas. The specific density and strength parameters in radial and axial compression were determined for the produced pastilles. The pretreatment notably reduced lignin content by 6.8–8.3%, which increased mechanical parameters, angles of internal friction, cohesion, shear, and consolidation stresses and positively affected agglomeration efficiency and increased pellet density. Values for the specific compaction work of treated biomass were higher than those of raw biomass (24.03 vs. 21.70 kJ kg⁻¹), correlating with the production of denser pastilles (1014 vs. 959 kg m⁻³). After pretreatment, enhanced structural properties of the biomass (lignin and hemicellulose components decreased, and cellulose content increased) facilitated increased methane yields, showing up to a 3.7-fold increase for pine and 2.9-fold for poplar UF particleboards. This research advances the potential for developing recycling and biogas technologies, offering novel insights into UF degradation via fungal pretreatment. The findings underscore the necessity for further detailed studies to analyse changes in resin content post-pretreatment and their impact on the properties of wood materials.