固定床颗粒层过滤性能分析及预测

使用两种滤料颗粒在一套冷态试验装置上考察了过滤气速和颗粒层厚度对颗粒层过滤性能的影响。结合颗粒层过滤宏观模型，分析了不同操作条件下粉尘比沉积率σ对颗粒层粉尘捕集能力偏离初始值程度F和过滤压降偏离初始值程度G的影响，然后预测了过滤效率和压降。结果表明，试验范围内，随着σ的增大，F呈现先增加后降低的变化趋势，而G逐渐增加。结合过滤气速u=0.2~0.6 m·s^-1、颗粒层厚度L=0.11~0.2 m条件下的试验数据拟合得到了F-σ和G-σ函数关系，过滤效率和压降的计算值与试验吻合较好，优于文献中相关公式，可为颗粒床过滤性能的预测提供参考。

Analysis and prediction of fixed granular bed filtration performances

The influences of superficial velocity (u) and granular layer thickness (L) on the granular bed filtration performances were investigated in a cold-state experimental apparatus using two kinds of filter media.Combined with the macroscopic model of granular bed filtration,the effects of the specific mass deposit (σ) on the deviation degree (F and G) of dust collecting ability and pressure drop with initial values under different operation conditions were analyzed.On this basis,the prediction of filter efficiency and pressure drop was performed.The results revealed that F increased at first and then decreased with increasing of σ,while G presented a linearly increase trend.The functional relationship between F(G) and σ was established by combination with experimental data under the condition of u=0.2~0.6 m·s^-1 and L=0.11~0.2 m.The calculations of the proposed formulas were in a good agreement with experiments,which were better than the formulas provided in the literature,and thus could provide some guidance for the prediction of performances of granular bed filters.