Bag membrane filter material is a kind of composite filter material. Its surface is a very thin (50 um thick) smooth porous (1.4 billion pores per square centimeter) expanded PTFE film. In order to be durable, the film is compounded on the tensile and anti-wear materials. Because the dust can not penetrate into the membrane during filtration, no matter the thickness of dust is all deposited on the surface of the filter material. Surface filtration does not need to establish a “filter dust layer” between the pores (space between fibers) of the filter material at all, while the industrial fabric filter material usually used needs to establish such a dust layer.
Performance:
(1) Dust removal rate: because the porosity and mass density of the membrane do not change after dust removal, the membrane filter material can achieve zero emission under the condition that the particle size of the filter dust is very fine.
(2) Permeability: the permeability of clean filter material is about 8% – 10% lower than that of general filter material (30% – 70%). It is understandable that the low permeability is caused by a thin film on its surface.
(3) Pressure loss: its pressure loss can be attributed to the pressure loss of the membrane, which is much smaller than that of the textile filter material during filtration. In practice, its pressure loss is about 980.7pa (100mmh2o).