An Andreae filter is based on the principle of inertia, where the particles are fed with air flow. The design of the filter means that the particles are trapped in v-shapes allowing the air to continue almost unhindered through holes at the top of the filter plate.
The filtration shape is very effective for particles, such as paint, glue, oil, grease, etc., all of which are liquid, and therefore adhere to the bottom of the v-shape.
As the air does not pass through the filter material itself, but instead has its own path, the static pressure remains at a low level. This means lower energy costs.
In addition to the low static pressure, this kind of filters also has a long life as there is no risk of fibre material blockage as in conventional filtration.