Exploiting torrefied rubberwood pellets for sustainable energy in Southern Thailand: Integrated techno-economic and environmental optimization

This study investigates the potential of torrefied rubberwood pellets (TWP) as a sustainable biofuel, using waste from southern Thailand's wood processing industry. A multi-criteria framework combining experimental analysis, CO 2 emission, and an Economic Environmental Index (EEI) was employed to optimize torrefaction conditions and evaluate industrial scalability. The optimal conditions were identified to be 288 °C for 30 minutes, resulting in a volumetric energy density of 16.10 GJ m -3 and an eco-efficiency of 0.16 %Y E (kg CO 2_eq /kg biomass) -1 USD -1 . This demonstrates a critical balance between energy quality and environmental impact. Compared to conventional wood pellets, torrefaction reduced CO 2 emissions by 27%. GIS mapping was used to plan regional logistics routes, while scenario analyses demonstrated enhanced profitability (EEI ratio: 2.73) and carbon credit opportunities, reducing 2,275 kg CO 2_eq per ton of coal replaced. The study establishes TWP as a carbon-negative biofuel suitable for power generation and cement production, supporting Thailand's transition to a circular bioeconomy. By bridging technological innovation with regional waste valorization, this research provides a replicable model for sustainable biomass utilization in tropical agro-industrial contexts.