The bag filter has the characteristics of high dust removal efficiency, large application range, and is widely used in industrial dust removal. But good products also need careful maintenance.
The bag filter has the characteristics of high dust removal efficiency, large application range, and is widely used in industrial dust removal. But good products also need careful maintenance. Today we talk about one of the most common problems encountered with dust collectors.
Let's briefly explain why the filter bag is blocked. The filter principle of the filter bag is achieved by using dense fiber holes above the bag. Particles with a particle size greater than a certain value cannot pass through. The tiny particles and gas can through this filter, the so-called cloth bag is actually blocked by the upper fiber hole, resulting in all gas and dust can not pass.
First, if the filter bag filter operating speed filter bag design standards, it will easily lead to micro-fine dust in the filter bag fiber inside, resulting in filter bag clogging.
Second, for highly viscous dust, you should reduce the speed of the filtered air, or increase the pressure of the pulse jet, or use an off-line pulse bag filter to clean the filter bag, but it is better to increase the filter area, in order to reduce the filtration speed, extend the life of the filter bag.
Third, the main causes of bad filter bag cleaning include: Frequent cleaning times, cleaning time is too long. Frequent cleaning times will tend to loosen the filter bag's fibrous tissue and increase the fine dust in the exhaust gas to clog the filter bag. Too long cleaning time will wash away the initial powder on the surface of the filter bag and affect the dust collection efficiency. However, if the cleaning time is too short and the dust on the surface of the filter bag has not been completely cleaned, the filtration will start immediately. The dust will gradually accumulate on the surface of the filter bag, causing the filter bag to clog. When this problem is solved, several times can be solved. Trial run to adjust.
Fourth, the reason of the filter bag damp: Poorly sealed bag filter body leaks, into the air containing moisture, compressed air used to blow dry cleaning is not clean, compressed air for cleaning is too cold and so on. In order to prevent the filter bag from getting wet, in the cold place, the compressed air used for cleaning can be increased in temperature, temperature, oil, and water, and the dust removal can continue for 10 to 20 minutes after the bag filter is stopped.
Fifth, water is a major factor in the clogging of filter bags of baghouse filters. The reason for moisture content is usually condensation at low temperatures, especially in the following situations:
1. To avoid improper boot. The bag filter should be pre-started and air-operated according to the specification procedure.
2. To avoid the boot when the dust collector resistance. When the filter bag is stopped, the condensate on the surface of the filter bag is restarted. In this case, a large amount of dust-laden air enters, and the high humidity causes the surface of the filter bag to become muddy. In order to prevent this from happening, the precipitator inlet dust air or pre-dust layer should be warmed up.
3. Avoid booting below dew point. The bag filter is prone to problems when it is operated below the dew point. If the intake air is not evenly distributed, local corrosion of the dust collector housing can easily occur. Therefore, the bag filter should be avoided to work below the dew point, and the insulated device should be used in time.
4. Air infiltration. Air infiltration often occurs in the dust collector's flange, access door or dust collector's mobile devices. If the seal is not strict, the outside air enters the bag filter, when dealing with high temperature exhaust gas, it will produce a low temperature zone inside the dust collector, resulting in low temperature condensation at the place, corrosion of dust collectors, causing moisture in the filter bag.