10.5071/19THEUBCE2011-VP3.1.16
Ammendola, P.
P.
Ammendola
Chirone, R.
R.
Chirone
Ruoppolo, G.
G.
Ruoppolo
Scala, F.
F.
Scala
Comminution Phenomena of Wood Pellets and Chips Under Combustion and Gasification Conditions
ETA-Florence Renewable Energies
2011
Conference paper
Biomass
2011
en
978-88-89407-55-4
4 Pages
application/pdf
Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, pp. 1973-1976
This work reports on a study, carried out in a labscale fluidized bed apparatus, on fragmentation and attrition of two biomass fuels, namely wood chips and wood pellets, under combustion and gasification conditions. The aim was to highlight the effect of their different mechanical strength on the fuel particle size distribution and overall carbon conversion. Primary fragmentation tests showed that for wood pellets limited fragmentation occurred during devolatilization, with a fragmentation probability around 30% and particle multiplication factor of 1.4. On the contrary, wood chips were subject to extensive fragmentation as witnessed by large values of the particle multiplication factor and of the fragmentation probability. Results of char attrition experiments carried out under inert, combustion and gasification conditions showed that the carbon loss by elutriation is critical only during gasification, especially for the wood chips char. A gasificationassisted attrition mechanism was proposed to explain the experimental results, similar to the well known combustionassisted attrition patterns already documented under oxidizing conditions. The higher mechanical strength of the wood pellets appears to be beneficial for reducing carbon elutriation and for obtaining a higher carbon conversion.
Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1973-1976