Filter Cloth Effect

Dust layer filtration mechanism:

In the filtration mechanism of the filter fiber, such as diffusion, gravity, inertia collision, electrostatic and other effects on the dust layer is present, but the main screening effect. When the bag filter begins to run, there is no dust on the new filter bag, and after a few minutes of operation, a thin dust film is formed on the bag surface. As the filter bag is made of fiber weaving, so the dust layer is not formed before the dust will be in the role of diffusion and other effects gradually formed in the fiber between the fiber bridge phenomenon. Filter bag fiber diameter is generally 20 to 1005m. Needle felt fiber diameter of 10-205m. Filter Cloth The distance between the fibers is mostly 10-305m, the bridge phenomenon is easy to occur. Bridge after the completion of the phenomenon of 0.3-0.5mm dust layer is often referred to as dust or a dust layer. In a dust layer above the accumulation of dust again said secondary dust layer.

Plain fabric filter cloth itself dust removal efficiency of 85% to 90%, the efficiency is relatively low. But the surface of the surface of the surface of the dust adhering to the accumulation, you can get more than 99.5% high dust removal efficiency. It is necessary to remove the dust, Filter Cloth the filter cloth surface residual 0.3-0.5mm thick dust layer to prevent the dust removal efficiency. The problem is how the dust collector is finished during the operation to keep the first dust layer retained, and only the second dust layer is removed. This problem is both a technical problem and a disposal experience for the design and manufacturing plant. Filter Cloth So you can say that the history of bag filter, is the gradual improvement of the history of continuous improvement. Based on the effect of the dust layer on the efficiency, the dust removal efficiency in the dust layer is drastically decreased. At the same time, the flue gas flows through this part due to the decrease of the pressure loss. Therefore, Filter Cloth after a few seconds the surface of the filter cloth and the formation of a dust layer, dust efficiency has increased, that is, each clear cycle can be discharged a certain amount of dust.

On the other hand, if the filter wind speed is designed properly, to the filter cloth surface filter layer has a certain pressure loss (often 1000 a 1500Pa), that is, Filter Cloth within the required time to reach a certain thickness of the filter layer, the time is proportional to the wind speed The Take the filter speed of n times, the required time is 1 / n, the number of times the dust layer must be removed at least n times per hour, in fact, must take into account the time required to clear (10 a 30s), should take n ten times. In addition, the use of non-woven needle felt as a filter cloth, generally can be used 1.5 to 2.5mm thickness, Filter Cloth this layer is equivalent to the previously mentioned a dust layer, it exists in the filter cloth inner layer.

Flue gas and dust from the surface of the filter through the penetration, while in some way to remove the dust, the two effects of the balance, the filter cloth in the inner layer (felt layer) to form a thickness of 0.5-0.7mm , Which is a layer of dust and filter cloth fibers, which is called an inner filter layer, which corresponds to the primary filter layer of the plain weave fabric. However, the flue gas is re-deposited on the surface of the filter cloth to become a secondary dust layer. So that the inner filter layer with the fiber intertwined with the secondary dust layer compared to its nature is very different, so only the secondary dust layer is removed, the inner filter layer is easy to completely retain, so the dust removal efficiency after removal of dust is not Will drop. The adhesion of the dust on the filter cloth is very strong when the filtration rate is 0.28 m /. , Filter Cloth The diameter of 105m dust particles in the filter on the adhesion can reach 1000 times the particle weight, 55m dust particles in the filter on the adhesion can reach the particle weight of 4200 times. So after the filter bag cleaning, the dust layer will continue to exist. The presence of the dust layer, so that the role of screening process greatly enhanced screening, filtration efficiency also increased. Dust layer formation of the mesh than the filter fiber gap is much smaller, the screening effect is obvious.

The formation of the dust layer is related to the filtration rate. When the filtration rate is high, the dust layer is formed faster. When the filtration rate is very low, Filter Cloth the dust layer is formed slowly. If you simply consider the dust layer of the filter effect, 'low filtration rate is not good. When the dust layer continues to thicken, it must be removed in time by means of cleaning, otherwise it will form too high resistance, or the automatic landing of the dust layer, resulting in dust "dust" phenomenon, reduce the effect of dust collection.