滤布材质及微观结构与透水性能的关系

Relationship between Material and Microstructure of Filter Cloth and Water Permeability

机织滤布的透水性能会直接影响过滤设备的生产效率。为理清滤布材质、微观结构与过水通量之间的相互关系,定制一批控制变量的滤布用于实验。对不同材质的滤布进行了FTIR,动、静态接触角和表面能测定,从机理分析了材质影响过水通量的关键性指标。对滤布微观结构进行了SEM表征,并分析了编织方式、厚度、孔径对过水通量的影响,建立了滤布微观结构与过水通量的半经验模型。结果表明:材质亲水性大小顺序为聚丙烯>聚碳酸酯>聚酰胺,对应的过水通量分别为6.34、5.75、5.46 m/min,亲水性强的材质具有更大的过水通量;微观结构中,过水通量大小顺序为缎纹滤布>斜纹滤布>平纹滤布,孔径、厚度分别与过水通量呈正、负相关关系,拟合的微观结构与过水通量的半经验模型可以为机织滤布的选型提供理论参考。

The water permeability of woven filter cloth directly affects the production efficiency of filter equipment. In order to clarify the relationship between material, microstructure of filter cloth and water flux,a dozen of woven filter cloth with control variables were customized for the research. FTIR, dynamic and static contact angles and surface energy measurements were used to evaluate the filter cloths of different materials. The key indicators affecting the water flux were analyzed from mechanism. The microstructure of the filter cloth was characterized by SEM, and the influences of weaving method, thickness and pore size on the water flux were analyzed. A semi-empirical model between microstructure of filter cloth and water flux was established. The results show that the hydrophilicity order of material is polypropylene>polycarbonate>polyamide, the corresponding water flux is 6.34, 5.75, 5.46 m/min, respectively. Hydrophilic materials have a larger water flux. The water flux order of filter cloths under different weaving methods is satin filter cloth>twill filter cloth>plain filter cloth. The pore diameter and thickness are positively and negatively correlated with the through-water flux, respectively. The semi-empirical model of fitted microstructure and water flux can provide theoretical reference for the selection of woven filter cloth.