Reasons for the low efficiency of air filter bags

The bag filter is a relatively mature product in the current market. According to our company's many years of experience in the production of dust collectors, several major factors affecting dust removal efficiency have been summarized in the design of the dust collector.

The main influencing factors are:

1. The nature of dust.

The dust removal efficiency of the bag filter is directly related to the size, weight, shape, electrostatic effect and dust concentration of the dust particles. According to Dongguan environmental protection experts, the dust removal efficiency is higher for dust with larger particles, heavier particles, irregular shapes and obvious electrostatic effects.

2. The performance of the dust air filter bag.

The performance of filter cloth has a great influence on dust removal efficiency and resistance. The filter cloth material should meet the following conditions:

1. It can block the passage of fine dust. The interlaced holes of the warp and weft threads of the fabric should be small, and the warp and weft lines themselves should be thin to increase the filtering area and reduce resistance;

2. The fluff of the fabric should be long and elastic, so that it can cover the holes and have a certain strength; 3. In order to facilitate cleaning with reverse airflow, the fluff of the fabric is located on the side that is in contact with the dusty air.

3. the influence of filtration speed

The lower the filtration rate, the easier it is to form a primary dust layer with a small particle diameter and a large porosity, and the more it can capture fine dust particles. When the filtering wind speed is too high, the penetration of the dust particles into the filter material will be aggravated and the filtration efficiency will be reduced. Of course, the penetration phenomenon can also be overcome by selecting a suitable filter material. In addition, for some filter materials, when the filtering wind speed changes within a certain range, the dust removal efficiency is almost unaffected.

4. The influence of the dust layer on the filter material. At the initial stage of operation of the bag filter, there is no dust layer on the new filter material. At this time, the ability to collect dust is low. As the filtering process progresses, the dust layer is gradually formed, and the efficiency of dust removal is Correspondingly, when the dust layer is completely formed, the filtration efficiency can reach more than 99%, and it also has a good trapping effect for fine dust particles smaller than 1μm.

5. Air leakage and resistance:

The theoretical calculation of the dust removal efficiency of the bag filter is 99%, but it cannot be achieved in the actual test, mainly due to the influence of air leakage and resistance. The lower the air leakage rate, the better the dust removal effect; the resistance has a certain influence on the dust removal effect of the electrostatic precipitator. Empty the filter bag to reduce resistance and improve the dust removal effect. The dust collecting hood should be as close to the furnace head as possible to make it easier for dust to enter the hood, increase the amount of dust collection, and reduce fugitive emission pollution.