Abstract
Characterization of biomass ash melting and thermal behavior is crucial to prevent and reduce ash related problems in biomass-fired boilers, In present work, ash melting behaviours of spruce saw dust and bark were investigated by simultaneous thermal analysis (STA), The decomposition stages of sawdust and bark biomass were characterized by four peaks, respectively, The four peaks are the first relatively small one at temperatures about 317-341 °C, a second large peak at 419-451 °C, a small third peak at 860-1000 °C and a small endothermic peak at 1290-1400 °C, DSC curves of bark sample at both heating rates were shifted towards lower temperatures than DSC curves of sawdust fuels, On average, the degradation process starts 5 °C earlier and the second exothermic peaks in both heating rates are found even 20 °C earlier, The remaining residue of bark samples was approximately two times higher than that of sawdust, The ignition temperatures of both spruce and pine bark were slightly shifted to higher temperatures compared to those of spruce and pine sawdust samples, STA experiments of exanimated biomass fuels indicated that their critical melting temperatures lie in the range of 860-1000 °C, The information obtained in this study qualifies the STA method as a suitable and rather simple method for the determination of ash melting and thermal behavior of woody biomass. © 2016 ETA-Florence Renewable Energies.
