关键词: 环流反应器, 气固体系, 空隙率, 颗粒速度, 颗粒环流速度

Abstract: The study and application of airlift loop reactor has been limited for gas-liquid and gas-liquid-solids system.The hybrid of gas-liquid loop theory with gas-solids fluidized bed is a creative exploration.In order to overcome the shortcoming of commercial gas-solids internal airlift loop reactor, a novel gas-solids annulus-sparged airlift loop reactor (ASALR) was proposed.Based on experiment and theoretical analysis, a model was proposed to predict the mean voidage of the annulus region.It was found that the mean voidage of the annulus region increased with increasing superficial gas velocity in the annulus.Particle velocity was considerably higher in the area close to the outer wall of the draft tube than that in the area close to the inner wall of the ASALR.The radial distribution of particle velocity in the draft tube region was remarkably influenced by the configuration of the ring sparger.In addition, particle velocity almost kept constant along the axial position.Unlike in annulus region, the migration of particles in the draft tube was dense-phase transport.The flow resistance of circulating particle was more significant in the top and bottom relative to that in the annulus and draft tube.Furthermore, the flow resistance in the bottom was primarily determined by the clearance of draft tube from the bottom of the ASALR and by the fluidization quality.A mathematical model was deducted in order to predict particle circulating velocity, which was found to increase with increasing superficial gas velocity in the annulus.

Key words: 环流反应器, 气固体系, 空隙率, 颗粒速度, 颗粒环流速度