September 13, 2021 | yourfilter GmbH
The different types of filtration
Two types of filtration are distinguished in particle filters:
- Surface filtration
- Depth filtration
Surface filtration:
The pores on the surface of the filter medium are very small. The particles cannot enter the filter medium. A dust layer, the so-called "filter cake," forms on the filter material. This filter cake can be cleaned off by air blasts, vibration, or shaking, so the filter is ready for a new cycle. These are the so-called "cleanable filters."
Examples: filter bags, filter cartridges, filter plates

Depth filtration:
The pores on the surface of the filter medium are somewhat 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 by shaking off, and the filters must be disposed of when they are fully "saturated."
Examples: filter mats, bag filters, cassette filters, particulate filters

Fig. 2: (Pre)-filter mats, particulate filters, cassette filters
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