Torrefaction integrated with pelletization has gained increasingly interest as it enhances the characteristics of fuel pellets (e.g. hydrophobicity and energy density). In current study, torrefaction of furfural residue pellets (FRPs) and sawdust pellets (SPs) was performed by employing tubular reactor furnace, and quality of pellets was compared. The characteristics of both types of pellets were significantly improved with increasing torrefaction temperature from 200 °C to 300 °C and residence time from 15 min to 30 min. The highest lower heating value of 23.78 MJ/kg and energy density ratio (1.27) for torrefied furfural residue pellets (TFRPs) and 26.76 MJ/kg and 1.46 for torrefied sawdust pellets (TSPs) were achieved at 300 °C and 120 min. Increasing torrefaction temperature and residence time, the volumetric energy densities of TFRPs increased from 25.69 (at 200 °C and 15 min) to 27.59 kJ/m³ (at 300 °C and 120 min), while those of TSPs correspondingly decreased from 20.81 to 16.69 kJ/m³. The highest true densities (i.e. 2.40 and 1.85 g/cm³) and porosities (i.e. 52 and 65 v %) of TFRPs and TSPs were achieved at 300 °C and 120 min, much higher than those of un-torrefied pellets. Moisture uptake of TFRPs and TSPs at 300 °C were only 1.4 wt% and 2.0–2.8 wt%, respectively, showing strong water-resistant ability. The crystallinity of cellulose in FRPs was found higher than that of SPs, while the crystallinity of cellulose in TFRPs was found lower than that of TSPs at same process conditions. FTIR showed that O-H bond was destroyed after torrefaction for both FRP and SP.

与制粒相结合的烘焙技术引起了越来越多的兴趣，因为它提高了燃料颗粒的特性（例如疏水性和能量密度）。在目前的研究中，采用管式反应炉对糠醛残渣颗粒（FRPs）和木屑颗粒（SPs）进行了焙干，并比较了颗粒的质量。随着焙烧温度从200°C增加到300°C，停留时间从15分钟增加到30分钟，两种颗粒的特性都得到了显着改善。在300°C和120分钟下，焙干糠醛残渣颗粒（TFRP）的最高较低发热量为23.78 MJ / kg，能量密度比（1.27）和26.76 MJ / kg，焙烧锯末颗粒（TSP）的能量密度为1.46。增加烘焙温度和停留时间，³（在300°C和120分钟），而TSP的相应值从20.81降至16.69 kJ / m ³。TFRP和TSP的最高真实密度（即2.40和1.85 g / cm ³）和孔隙率（即52和65 v％）在300°C和120 min时达到，远高于未焙烧的颗粒。TFRP和TSP在300°C时的吸湿率分别仅为1.4 wt％和2.0–2.8 wt％，显示出强大的防水能力。在相同的工艺条件下，发现FRPs中纤维素的结晶度高于SPs，而TFRPs中纤维素的结晶度低于TSP。FTIR显示，在FRP和SP焙干后，OH键被破坏。