September 13, 2021 | yourfilter GmbH
The different types of filtration
With particle filters, a distinction is made between two types of filtration:
- Surface filtration
- Depth filtration
Surface filtration:
The pores on the surface of the filter medium are very small. The particles cannot get into the filter medium. A layer of dust, the so-called "filter cake", forms on the filter material. This filter cake can be cleaned off by blasts of air, vibration or shaking so that the filter is ready for a new round. These are the so-called "cleanable filters".
Examples: Filter hoses, filter cartridges, filter plates
Depth Filtration:
The pores of the surface of the filter medium are slightly larger. The particles can penetrate into the filter medium and are “held” there by the fibers of the filter material. The filter material cannot be cleaned and the filters must be disposed of when they are fully “saturated”.
Examples: Filter mats, pocket filters, cassette filters, filters for suspended matter
Fig. 2: (Pre) filter mats, HEPA filters, cassette filters
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