Engineering

Industrial filters achieve the highest separations of all separators and thus the lowest output concentrations below 1 mg / m3. Industrial filters differ according to the shape and technical design of the filter elements. In practice, we distinguish filters(bag house, cartrige, hose, lamellar etc.).

  Industrial filters can also differ in the way the filter elements are used. Regeneration of industrial filters is performed in several ways. Pulse regeneration is most often used during filter operation, where the energy of compressed air is used (especially for hose and cartridge filters). In the case of bag filters, regeneration by backwashing is used in particular, where part of the filter is shut down for a short time and blown out with external air. One of the most important factors in the design of filters is the correct choice of the material of the filter element.   When choosing a material, it is necessary to consider several basic aspects, such as the structure of the filtering layer (fibre diameters, porosity, layer thickness, surface treatment), mechanical, thermal, chemical and electrical properties of the fabric. The separating capabilities of the filter fabric are determined by the structure of the filtering layer. The separation process in industrial filtration consists of three phases.   In the first phase, the particles are separated on the individual fibres of the front part of the filtering layer by the same principles as in air filtration, ie mainly by diffusion, inertia and interception. In the middle phase, the particles in the layer are mostly separated on already separated particles, and the fibres are bridged by the resulting chains and surface clusters of particles. In the final stage, the pores on the front side of the layer are filled and the separated particles from a filtration cake on the surface of the layer in the form of a layer of separated particles, which further acts as a porous granular layer for separating other particles. As the thickness of the filtration cake increases, the pressure drop increases. After exceeding a certain pressure loss, it is necessary to remove the layer of particles (filtration cake) - by the regeneration of the filtration material or regeneration of the filter. A large part of industrial filters are occupied by hose filters, the so-called "bag filter", where hoses can have different shapes (round, oval). These filters are used from flows of 1000 m3 / h to flows in the order of one million m3 / h, so-called "bag-house filters".