Abstract: The particle density and bulk density of biomass and three kinds of inert particles were measured using MDMDY-300 Automatic Density Meter and traditional volume method, respectively. The minimum voidage and minimum fluidization velocity of biomass monocomponent and three inert particles were observed in the plexiglas bed. The results indicate that the monocomponent particle density is almost independent from particle size, while the bulk density reduces with increment of particle size. The minimum voidage decreases when fine particles are introduced and reaches a minimum value at the fine particles of about 30%(v/v). The minimum voidage of bi-component system starts to increase with fine particles increasing. Moreover, the greater the difference in particle size, the more obvious this trend. The initial, minimum and full fluidization velocities of bi-component system decrease with increment of the volume fraction of fine particle. It is similar to the minimum voidage, the minimum fluidization velocity decreases slowly when the volume fraction of fine particles is more than 30% or so.

Key words: biomass, inert particles, bicomponent system, fluidization characteristics