What is a biotrickling filter?
A biotrickling filter is a biological reactor where polluted air can be biologically treated. The principle of a biotrickling filter is as follows: waste air is contacted with a scrubbing solution (usually water) in a column packed with random plastic material (Rashig or Pall rings, balls etc.), lava rock, open pore foam or other inorganic support material. On the surface of the packing, a biofilm of pollutant degrading microorganisms forms which aerobically degrade the absorbed pollutants. Since the packing is made of an inert material, a continuous supply of mineral nutrient (N, P, K, +traces) is needed. In summary, a biotrickling filter is a biological scrubber where simultaneous absorption and biodegradation is achieved.
