Fluidized bed torrefaction of biomass pellets: A comparison between oxidative and inert atmosphere

摘要: Abstract The paper reports on an experimental study aimed at investigating the potential of performing biomass torrefaction using air instead nitrogen as a carrier gas, which allows reducing operating costs upgrading biomass. Specifically, performances oxidative and non-oxidative treatments were comparatively investigated by commercial wood pellets olive pomace feedstock. Batch tests three different temperature levels (200, 230 250 °C) performed in laboratory-scale fluidized bed reactor fixing reaction time equal to 15 min; this allowed investigate impact atmosphere on: a) distribution main output products process (torrefied solids, condensable volatiles permanent gases); b) properties torrefied fuel (i.e., proximate composition, ultimate composition calorific values); c) terms mass energy yields solid product; d) quality densities, hardness (shore D) non-standard durability index. Fluidized-bed also complemented non-isothermal thermogravimetric measurements (TG/DTG/DSC) both atmospheres. Results show that, under same conditions, performance product) are worse than that treatment, particularly case pellets. This is mostly consequence higher degradation rate triggered reactions. On other hand, physical density, durability) obtained better those via torrefaction. A similar behavior, however, was not observed woody fir confirms feedstock-sensitive process; particular, non-woody can be environments, whereas more suitable for Since treatment has been so far, findings work useful highlight advantages related use such technology specific application.