1. Deep filtration
This kind of filter material is relatively loose, and the gap between fiber and fiber is large. For example, ordinary polyester needled felt has a gap of 20-100 μm. When the average particle size of the dust is 1 μm, during the filtering operation, a part of the fine particles will enter the filter material and stay behind, and the other part will escape through the filter material. Most of the dust adheres to the surface of the filter material to form a filter layer, which will filter the dust in the dust-laden airflow. The small particles entering the filter material will increase the resistance and harden the filter material until it is scrapped. This type of filtration is usually called deep filtration.
2. Surface filtering
On the side of the loose filter material that contacts the dust-containing gas, a layer of microporous film is bonded, and the gap between the fibers is only 0.1-0.2 μm. If the average particle size of the dust is still 1 μm, almost all the powder Will be blocked on the surface of the microporous membrane, fine dust can not enter the inside of the filter material, this filtering method is usually called surface filtration. Surface filtration is an ideal filtration technology, it can further improve the efficiency of dust removal, reduce the pressure loss of the filter material, and greatly save the power consumption of the dust removal system. If the fiber of the filter material is very thin, after a special process, it can not only maintain a certain degree of air permeability, but also reduce the gap between the fibers. Although this filter material is not coated on the surface, it is difficult for the fine particles in the dust to enter the filter material. This kind of filter material without multiple membranes can also be used for surface filtration. The filter material used to make the filter cartridge, there are multiple-membrane filter media and non-multi-membrane filter media, whether surface filtration can be performed depends on the selected filter material.
Post time: Sep-26-2021