Deduction and application of filtration and cleaning indices for aerosol filtration operations using nonwoven fabrics as filters

Abstract

The characteristics and properties of fabrics used to make filters, as well as the operation conditions, affect filtration and filter cleaning performance. Accordingly, it is appropriate to group, as done here, such characteristics in dimensionless numbers in order to compare different fabrics used in the filtration of gases in a simple way.In this sense, the authors have previously proposed certain parameters generically termed filtration indices and here these were deduced using dimensional analysis. What we have named cleaning efficiency index is also considered to evaluate the efficiency of a cleaning system. These parameters, and others widely discussed in the literature, were applied to the experimental results obtained by the authors in the filtration of fly ash aerosols with different nonwoven fabrics. Additionally, certain experimental results of other authors are used. The results show that the filtration and cleaning indices may be useful for the comparison of fabrics required for specific applications.

On the filtration performance of dust-loaded trilobal fibers

“…The effect of particle deposition on the filtration performance (i.e., collection efficiency and pressure drop) of fibers with circular cross-section has been investigated previously in many studies (e.g., [7][8][9][10][11][12][13][14][15][16]). Although trilobal fibers are becoming increasingly more available [17][18][19][20][21], the literature is very scarce (and controversial sometimes) when it comes to using such fibers for aerosol filtration [22][23][24][25][26]. In fact, there are too many unanswered questions with regards to the actual advantage of such fibers over fibers with circular cross-sections.…”

An efficient and continuous filter operation for dust‐laden flue gas based on a self‐cleaning stainless steel weaved filter

“…The filter is woven by bundled threads twisted with the short ceramic fibers produced via melt‐blowing or spinning method or compressed with fusion binder 14–16 . During the filtration process, fine particles tend to be captured by the ceramic fibers forming dust cake and are not easy to be removed by cleaning techniques such as high‐pressure reverse jet pulses and mechanical vibration, resulting in increase of pressure drop and reducing lifespan of the filter 17–22 . The frequently cleaning procedure hinders the continuous filtration and causes damages and leaks of filter 23 .…”

“…[14][15][16] During the filtration process, fine particles tend to be captured by the ceramic fibers forming dust cake and are not easy to be removed by cleaning techniques such as high-pressure reverse jet pulses and mechanical vibration, resulting in increase of pressure drop and reducing lifespan of the filter. [17][18][19][20][21][22] The frequently cleaning procedure hinders the continuous filtration and causes damages and leaks of filter. 23 To investigate mechanism and the influencing factors of adhesion between the fibers and the particles, material properties of fibers are studied.…”