Filters of type BHF

Filter consists of body divided into the chambers of non cleaned and cleaned gas, filtering elements (framework type), valve section with control electromagnets and control of regeneration of bags. Dusty air through upstream fairing gets into chamber where filtering bags are located. The dust is retained on a filtering surface of a material, and the cleared gases leave through the top open parts of bags for cleaning air chamber. Filtering bags are made on the specialized sewing equipment (see the catalogue of “NPP "Folter") from highly efficient nonwoven filtering fabric.

Bags can also be made from conductive materials for removal of a static charge. Regeneration of filtering bags is carried out periodically on the set cycle without switching-off of filter by a one-way pulse purge with compressed air getting into bags from above through apertures in blowing-through collectors. The filter has gauge of pressure resistance, which signalized then filter reaches certain resistance automatically. Pulse duration and frequency of regeneration cycles is set with regeneration controlling device included in the filter delivery package. System of regeneration is designed for use of compressed air at pressure 0.3 – 0.6 MPa (3-6 kgs/cm2 ).

The compressed air incoming to filters, should be dried and cleaned. Filters for catching explosive dusts are equipped with safety valves with a destructible membrane. Filter starters should be mounted in not explosive room. To provide normal operation of the filter, unloading of the caught dust from the bunker should be carried out periodically or constantly (depending on initial dust content). If dust unloading is done when filter is in operation, hermetic sealing of discharge aperture should be provided. It is performed by penstocks. Installation of other sealing arrangements is possible. For operation of filters with 2 or 3 bunkers, conveyer screws (by special request) that empty bunkers and unload dust at the same place are used. To seal conveyer screw it is necessary to install penstock or other sealing/unloading device at the unloading outcome.

By request filter(s) can be equipped with system which will turn on: - signaling system and protection of filter against high temperature of cleared gases; - control over dust unloading devices of one or several filters. Automatic system is capable of sending information to the top level for control of system of air clean with technology which it serves.