Biofilter, for exhaust gas flows, has felt layer flanking biofilter materials and fluid delivery unit to prevent drying of filter material and improve its atmosphere

摘要

The biofilter to clean a gas medium, and especially an exhaust gas, has a housing (1) containing the biofilter material (8,12). The filter material (12) in the gas flow has a unit (11) to deliver a fluid. The fluid delivery unit (11) is in front of a second layer (8) of biofilter material, in the gas flow direction. The fluid delivery unit (11) is covered on both sides by a felt (9,10). The gas medium flows into a chamber (5) in the housing (1), and then through a grid (7) before reaching the initial biofilter layer (12) or the fluid delivery unit (11). Fertilizer and/or caustic soda is added to the fluid. The fluid delivery unit (11) has a ring channel with parallel connecting channels, with a pressure reduction unit before and/or after a valve. An Independent claim is included for a gas cleaning operation, where additives to the fluid set it to an optimum pH value, and can also include a nutrient for micro-organisms.