Packed column Trickling filter

Waste gas is first drawn in through the air/water separator, used to remove impurities in the air such as water droplets, solid particles, etc. The effluent then travels to the trickling filter, which is a packed column of very porous polymer material. The use of a polymer as the packing material enhances mass transfers between the liquid and gas. The polymer can fix a large culmre of specific bacteria capable of degrading contaminants found in the liquid phase. The trickling filter is followed by a compost-based biofilter that removes residual contaminants. 

Packed-Bed Fixed-Film Systems These systems were originally termed anaerobic trickling filters because the first systems were submerged columns filled with stones run under anaerobic conditions. A wide variety of packed media is now used ranging in size from granules 40 mesh to 7.5-cm (3-in) stones. Many systems use open structure plastic packing similar to that used in aerobic trickling filters. 

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