The active carbon is a highly porous material, whose activity is directly proportional to its surface porosity. The solvent contained in the air to be filtered is then condensed and retained by capillarity in the active coal itself. The adsorption capacity is proportional to the surface and strongly influenced by numerous factors such as the concentration of the solvent to be filtered, the humidity, the temperature, the crossing speed, the contact time and the activated carbon particle size employed.
Thanks to the size and cubic construction form the filter, in addition to ensuring a high filtration efficiency, it ensures a significant duration of the charge of active coal provided.
The activated carbon filter has been designed to get a crossing speed of 0,3 seconds and contact time of 1 second. This kind of operating principle is obtained by inserting two beds of activated carbon vertically into the cubic structure.
Air with volatile organic compounds enters the central part of the filter and expands into the quiet chamber. Air is forced by depression of the fan to pass through the two activated carbon beds, which are well filled, and it goes out from the lateral connecting socket. it is possible to built smaller versions with one activated carbon bed only, whose operating principle and characteristics such as speed and contact time remain the same. Air will be expelled from the outside through the chimney. The filter is not equipped with pre-filtering, solid compounds in the air must be retained by means of other filtering systems.
The filter is made entirely of a very thick carbon steel sheet, opportunely worked and treated to make it last a long time. The filter is equipped with inlet and outlet air flow, support legs, inspection doors, carbon exhaust valves.