Experimental Results o Mass and Energy Yield Referred to Different Torrefaction Pathways

The purpose of the present work is to investigate the influence of significant process parameters on the final properties of torrefied woods. Two types of woody biomass have been selected: biomass as production waste and biomass as raw wood. The biomass samples are subjected to torrefaction in a small plant capable of about 200 gr of biomass, directly flushed by nitrogen heated at selected temperatures by pushing it into an electrical resistance. The following process conditions have been selected: four different temperatures representative of light to severe torrefaction conditions: 230, 250, 280, 310°C; three residence time values of 30, 60 and 90 min; different selected fluxes of nitrogen, utilized as carrier gas, in the range from 40 to 70 lt•min-1 The final aim of this experimental activity consists in finding the effective set of the indicated parameters that maximizes the LHV of the obtained torrefied woods and their effects on fundamental properties such as: moisture, elementary and ash analysis, fiber analysis.