旋流振动流化床干燥性能的研究

Investigation on drying performance of revolving vibrated fluidized bed

文章以聚四氟乙烯粒子和蔗糖为物料研究了旋流振动流化床的流体力学及干燥特性,并与振动流化床的各种特性进行了对比。实验在一个干燥室直径为240 mm的小型圆筒振动流化床中进行,采用斜孔分布板使床内产生旋流。实验结果表明:在空气分布板开孔率相差不多的情况下,物料流化以前,旋流振动流化床的床层压降要大于普通振动流化床,一旦物料达到正常流化状态以后,2种振动流化床的床层压降相差不多;旋流振动流化床可以降低物料的临界含湿质量分数。

The hydromechanics and drying properties of vibrated fluidized bed （VFB） with oblique and straight holes distribution board were studied. The experiment was performed in a pilot scale vibrated fluidized bed with the diameter of cylindrical drying chamber D = 240 ram. An air distribution board with oblique holes was used to generate revolving air flow. Tefon particles and cane sugar were used as material. The results indicate that at the approximate open area ratio, the pressure drop of revolving VFB is higher than that of common VFB before the fluidization of the material. Once the material is fluidized well, the pressure drops of these two kinds of VFB are identical. The revolving VFB can lower the critical moisture mass fraction of the material.