In continuous rainy and heavy fog or frequent sandstorms, the self-cleaning air filter will often have a resistance greater than 1200Pa, or even seriously exceed the standard. The long-term occurrence of this situation will endanger the safety of the equipment and make the operation of the air compressor deviate from the normal working condition, reduce the intake air volume, increase the operating cost, and even cause the air compressor to surge.

The filter material of the self-cleaning air filter is generally made of wood pulp fiber paper filter paper. This filter paper is made of multi-layer thin paper. The average micropore of each layer of paper is about 20-70μm, and the micropores are interlaced Arranged vertically and horizontally, it has a certain degree of air permeability. The resistance value of air passing through the filter paper is small at a low filtration speed, and this kind of filter paper works better in a dry environment.

However, in continuous rainy and foggy weather, the relative humidity of the air is high, and the filter paper of the self-cleaning air filter expands after the fiber is damp, which shrinks or blocks some micropores. If the filter paper of this kind of filter has been used for a period of time, there will be dust on the outer surface of the filter paper and the paper core layer, and it will expand and block the micropores after being damp, so that the air permeability of the filter paper will be greatly reduced and even the tube will be pasted. The effect of self-cleaning and dust removal is also greatly reduced under lower backflushing pressure.

In order to solve the problem of high resistance in this kind of weather, the following countermeasures can be adopted: in the south of my country, the relative humidity is relatively high along the river, coastal areas or foggy areas, and the selection of filters and filter cartridges should be adapted to the local Climatic conditions. At the same time, it is necessary to increase the margin of the actual gas treatment, and the filter cartridge should use a composite fiber filter cartridge.

Common self-cleaning air filters can be divided into dry type and wet type according to the dust removal mechanism. The filter principle of the wet self-cleaning air filter is to rely on the oil film to adhere to the dust in the atmosphere to achieve the purpose of dust removal, but the filter accuracy is low and there is oil in the airflow.

Dry self-cleaning air filter is a kind of air filter that has the effects of gravity, inertial diffusion, contact blocking, electrostatic adsorption, etc. when the air passes through the surface and inner layer of various animal, plant or chemical fiber fabrics, so that the dust in the air stays in the filter material and filter paper. Outside (a dust film is established inside), to achieve the purpose of dust removal.