Co-gasification of rice husk and woody biomass blends in a CFB system: A modeling approach

Abstract

In the present study, co-gasification behaviors of rice husk (RH) and blends of two woody biomasses, sawdust (SD) and bamboo dust (BD) in a circulating fluidized bed (CFB) system were studied by using ASPEN plus software. The gasifier performance was evaluated in respect of the gas yield and its higher heating value (HHV), in addition to the char conversion efficiency (CCE) and cold gas efficiency (CGE). The present study effectively showed that the blending of biomasses significantly improves the producer gas quality in terms of H2 production and energy output, as well as the gasifier performance indicators. RH + SD blend showed both the highest higher heating value (4.79 MJ/Nm3) and H2 content (12.51 vol %) at 900 °C and ER of 0.24. The simulation results also showed that the gas yield was the highest for RH + BD blend (1.75 Nm3/kg) followed by RH + SD blend (1.73 Nm3/kg) and then RH (1.41 Nm3/kg) at 900 °C. The highest HHV of RH (4.71 MJ/Nm3), RH + SD (5.17 MJ/Nm3) and RH + BD (5.39 MJ/Nm3) were also obtained at 800 °C and ER of 0.19. Change in the steam/biomass (S/B) also showed a slight variation in gasifier performance parameters.