滞留率是确定流化干燥死床点的重要参数。针对气体分布板开直孔和开斜孔的惰性粒子流化床干燥器，以洗衣粉悬浮液为对象，考查了进料量、惰性粒子直径、进风温度、静床高、进风速度以及物料初始浓度对干燥器滞留率的影响，分析了气体分布板开直孔和开斜孔时干燥器滞留率的大小，并以气体分布板开斜孔为例，测定了干燥器的生产能力与板开孔率之间的关系曲线。结果表明，滞留率随进料量和物料初始浓度的提高而增大，随惰性粒子直径、进风温度、静床高和进风速度的提高而减小；若将气体分布板的孔道由直孔改为斜孔，并在此基础上适当增加板的开孔率，可有效降低干燥器的滞留率，提高干燥器的生产能力。

The value of detained mass of material is important for researching the dead bed point of fluidized drying. In order to acquire the effect law of structure of opening hole in gas distributor on detained mass of material, the drying processes of detergent suspension liquor were investigated in the inert particle fluidized bed drier. The curves of detained mass of material for drier with vertical-hole distributor and tithed-hole distributor were measured and compared under the same experimental parameters, such as feed volume, diameter of inert particles, gas temperature of entrance, height of static bed, gas rate of entrance, and concentration of material. Based on the result, the relationship data of drier with tilted-hole distributor were determined between the production capacity and the hole ratio of distributor. The results show that the detained mass of material increase with adding the feed volume or concentration of material, and decrease with adding the diameter of inert particles, gas temperature of entrance, height of static bed, or gas rate of entrance. In addition, changing the hole shape of distributor from vertical-hole to tilted-hole and adding the hole ratio of distributor, can help drier reduce the detained mass of material and enhance the production capacity.