带导流管多层流化床流体力学特性实验研究

多层流化床的应用范围受操作可调性和稳定性等因素限制。在改变传统筛板结构的基础上,研究了传统穿流板多层流化床和导流管多层流化床床层压降随表观气速和进料速率的变化规律,实验结果表明,导流管多层流化床不仅大幅减小了床层压降、提高了床体处理能力和可调范围,而且也改善了物料的流化质量。此外,当料层达到一定高度时,导流管多层流化床还具有喷动流化床的特性,同时导流管还具有溢流物料的作用,进一步加大了气固传质效率和床体处理能力。在流体力学分析的基础上,推导出导流管多层流化床床层压降的关联式,得到了床层压降随进气气速和进料速率的关系,与实验数据基本吻合。

Experimental study on hydrodynamics of multistage fluidized bed column with a draft tube

The applications of a multistage fluidized bed is limited by the adjustability of operation and stability of operation and so on.A small-size multistage fluidized bed with draft tube was employed to obtain hydrodynamic data in a range in operation condition.The multistage fluidized bed with draft tube exhibits properties different from a conventional one,such as lower stable pressure drop,higher disposal capacity and adjustable range and especially improving the fluidizability of the material.Besides,a multistage fluidized bed with draft tube possesses the characteristic of a spout-fluid bed and the function of flooding material when achieving a higher material level,thus further increasing the diathermanous efficiency and the disposal capacity of column.Finally,based on hydrodynamics analysis,the pressure drop characteristics with solid flux and gas velocity were summarized and simulated,the simulated results were agreed with the experimental data.