The difference between the deep filter material, the surface filter material and the surface filter material
Deep filter material：Such as needle felt filter bag, the pore and dust particle size, the filtering process to filter dust now surface to form a layer of porous layer of dust in the early to achieve better filtering performance, filtering dust embedded in the filter pore, dust bag permeability reduced, resulting in filtration resistance rise, but lower than the efficiency of cleaning cloth the state has improved significantly, the fiber thickness and needling density, density (weight) directly affects the performance of the filter cloths.
Surface filter material：The surface is ultrafine fiber layer or ultrafine microporous membrane. The pore size is smaller than the particle size of flue gas dust. When the flue gas passes through the filter cloth, the dust is arrested on the surface of the filter material, and the dust collecting efficiency of the surface filter material is high, and the effect of ash cleaning is good. All kinds of film mulching filter materials belong to this kind. But the membrane filtration capacity of the film and the adhesive force of the film and the base cloth directly affect the performance of the filter cloth. Once the membrane is destroyed, the performance of the dust bag is dramatically reduced.
Surface filter material：A gradient fiber layer structure, also called gradient filter material, is used. The radial section shows that the front layer is ultrafine fiber, and the latter layer is a coarse fiber layer. The fiber has a gradually expanding tubular ladder structure according to the air flow direction. The experiment shows that the material is efficient, the resistance is low, and the effect of ash cleaning is good. Spunlaced cloth and gradient fiber composite filter material all belong to this kind. At present, this kind of filter material has developed rapidly. The difference between the fineness of the spunlaced fiber and the other fibers is several times, and the filtration performance of the filter material is worth looking forward to, and the greatest advantage of the filter material is the obvious effect of collecting fine particles.
The deep filtration mechanism of dust filter bag, embedded deep in the dust filter, first layer under the action of improving filtering performance but also increase the power loss of the system, thus greatly increase the cohesive force in the dust filter surface, cleaning and regeneration process need greater strength to counter force. Taking the pulse cleaning method as an example, the amount of ash cleaning gas and the dust removal pressure in the deep layer are obviously higher than those of the other two kinds of filter material. In contrast, the filter material of surface filtration and surface filtration has better filtration performance.
In summary, the braided structure filter is the main method to improve dust bag filter technology, in order to meet different demand conditions, special performance of filter by using the postprocessing means of adjustment, can improve dust bag filter performance and use effect.