Optimization of Torrefaction Parameters for High Energetic Yields

Abstract

Torrefaction parameters for Tectona grandis (Melina wood) were optimised using a 2-level full factorial design (FFD) at temperature (240 - 300°C), residence time (30 - 60 min) and particle size (2 - 6 mm). The optimum parameters for high energetic yield obtained were temperature of 260℃, residence time of 60 minutes and 2 mm particle size. temperature was found to have greatest influence on the combustion properties of the Tectona grandis sample. The results showed that the volatile matters and moisture contents of the raw biomass increased from 79.26 to 54.90% and 7.23 to 2.87%, respectively, while the fixed carbon and HHV increased from 11.73 to 40.43% and 18.73 to 23.10MJ/kg, respectively after torrefaction at optimum conditions. This indicates that the torrefied Tectonas grandis has better energetic yields and thus can be employed in energy generation and metallurgical purposes.