Filter bag is a commonly used filter product for filtering air dust and industrial dust collectors, especially suitable for dry low concentration dust. Today, we will share the impact of oil content in dust on the service life of filter bags!

Current situation: Owners have reported that the resistance of the filter bag has risen to the pressure difference alarm value after about 10 days of use. After removing the filter bag and observing that there is not much dust on the surface, it is preliminarily judged that the dust contains oily components! ‍‍

On site investigation: Upon visiting the property owner's site, it was discovered that there were obvious points of oil mist generation around, but they were not visible to the naked eye. Therefore, we need to provide further verification!

Laboratory verification: 1 Appearance inspection of filter bag:

(1) Inspect the appearance of the filter bag, ensure that the bubble point is full and the flow channel is clear, indicating that there is no problem with the production process of the filter bag and that there is no excessive resistance in the structure of the filter bag.

(2) Dark impurities accumulate on the surface of the filter material and are very difficult to blow off.

2. Physical indicator testing:

(1) The air permeability of the problematic sample drops sharply, only one tenth of that of the clean sample, which is the fundamental reason for the increased resistance of the filter bag.

(2) The weight of the problem sample has increased, considering the accumulation of surface impurities, which is a normal value.

3. Analysis of problem samples:

(1) In addition to particulate impurities, there are a large number of impurities deposited on the surface to form a film.

(2) The main reason for the decrease in air permeability of the filter material and the high resistance of the filter bag is the clogging of the pores in the nanofilm caused by film-forming impurities.

Conclusion: (1) Surface filter materials exhibit excellent anti blowing and dust removal performance for small, dry, and non viscous particle impurities. For viscous impurities, due to their difficulty in backblowing, impurities are prone to accumulate on the membrane surface, causing a rapid increase in filter bag resistance and a shortened lifespan. (2) For working conditions with viscous/oily impurities, it is recommended to use oil resistant filter materials.