The dust removal efficiency is mainly affected by dust characteristics, filter characteristics, accumulated dust load on the filter bag, and filter wind speed.
1. Dust particle size directly affects the dust collection efficiency of bag filter. For dust particles above 1μm, the dust removal efficiency can generally reach 9.5%. In dust particles smaller than 1 μm, dust removal efficiency of 0.2-0.4 μm is the lowest. Regardless of the clean filter or dust filter, there is a similar situation. This is because for the dust particles in this particle size range, several kinds of dust trapping effect are in the low value region.
Dust particles carrying electrostatic charges also affect the dust removal efficiency. By using this feature, the dust can be charged in advance, so that high dust removal efficiency can be obtained for fine dust.
2. The structure type of the filter material and the condition of the surface treatment have a significant influence on the dust collection efficiency of the bag filter. Under normal circumstances, the efficiency of dust removal from the woven fabric filter is low, especially when the dust layer on the filter is not established or destroyed; the needle felt filter material has a high dust removal efficiency; and the latest The appearance of a variety of surface filter materials can achieve the desired effect of “zero emissions”.
3. The effect of accumulated dust load on the filter material is only significant when using woven cloth filter material. At this point, the filter material acts more as a support structure, and the main dust filter function is the dust layer on the filter material. After a period of time when the new filter material and cleaning are used, the dust removal efficiency is higher. low. However, for the needle felt filter material, this effect is small, and almost no effect on the surface filter material.
4. The effect of filtration wind speed on the dust collection efficiency is also reflected in the condition of woven cloths. The smaller filtration wind speed helps to establish a dust layer with small pore diameter and high porosity, thereby improving the dust removal efficiency. Even so, this effect can be rendered insignificant when using a napped woven cloth filter. When using a needle felt filter or surface filter material, the effect of the filter wind speed is mainly reflected in the pressure loss of the dust collector rather than the dust removal efficiency.