Collection efficiency is mainly affected by dust characteristics , filter characteristic , the accumulation of dust load on the filter bag , filter wind speed and other factors . 1. Bag house dust size directly affect the collection efficiency. For more than 1μm dust collection efficiency in general can reach 9.5%. Dust particles less than 1μm in order 0.2-0.4μm dust collection efficiency minimum . Whether clean filter or dust filter has a similar situation. This is because these particles in this size range , the effect of several traps dust, are at a low value area . Dust particles carry an electrostatic charge also affects the collection efficiency. Using this feature , you can make a pre- charged dust , fine dust and thus can achieve high collection efficiency . 2. The filter structure type , the condition of the surface treatment has a significant effect on the collection efficiency of bag filter . In general , low collection efficiency woven fabric filter , especially when the layer of dust on the filter has not been established or damaged condition especially ; needle felt filter has a high collection efficiency ; and the latest various surface filtration material appears you can get close to the desired effect , ” zero emissions” . 3. The accumulation of dust loading on the filter affects only under the conditions of use of woven filter was more significant. In this case the filter more often plays a supporting role in the structure , but whose main role is to dust accumulation of dust on the filter layer , within a certain period of time with a new filter after cleaning and collection efficiency are more low. But for the needle felt filter , the less affected , it is almost completely useless on the surface of the filter material . 4. Effect of filtration velocity on the dust removal efficiency is also more performance under conditions of woven , smaller pore filtration velocity helps to build small and high porosity of the dust layer , thereby improving collection efficiency. Even so , when the surface napped woven fabric filter, also allows this effect becomes significant. When using the needle felt filter material or surface filtration , filtration velocity impact mainly in the dust collection efficiency of the pressure loss , rather than respect .