Fluidization Characteristics of Rice Husk in a Bubbling Fluidized Bed
2006 (English)In: 19th International Conference on Fluidized Bed Combustion, 2006Conference paper (Refereed)
The fluidization characteristics of rice husk was investigated experimentally in a 0.17 m ID, 0.9 m high laboratory scale fluidized bed by analyses of mean bed pressure drop, pressure fluctuations, power spectrum of pressure fluctuations, and visual observation with a digital camera. The results show that pure rice husk (rp = kg/m3) cannot be fluidized uniformly due to the occurrence of severe channeling. One of the possible methods to facilitate fluidization is to mix rice husk with an easily fluidizable solid. In this study, mixing 700 mm glass bead particles (rp = 2500 kg/m3) with rice husk improved the fluidization characteristics significantly. The minimum fluidization velocity of the binary mixture decreased and approached to that of glass bead particles as the mass fraction of the rice husk in the mixture was decreased. Power spectrum of pressure fluctuations was used to determine the quality of fluidization and estimate the onset of fluidization for the rice husk-glass beads mixture. Furthermore, it was found that with intermittent (pulsed) supply of fluidization air, the fluidization characteristics of pure rice husk could be substantially enhanced. In a frequency range of 0-10 Hz, flow pulsation resulted in turbulent bed-like behavior with improved gas-solid contact.
Place, publisher, year, edition, pages
fluidization, biomass, bubbling fluidized bed, rice husk, minimum fluidization velocity
IdentifiersURN: urn:nbn:se:umu:diva-20028OAI: oai:DiVA.org:umu-20028DiVA: diva2:207989