SMALL-CAPACITY BIO-AERATION PLANT

摘要

The invention concerns a small-scale biological sewage treatment plant operated by fluid bed/biofilm technology for treating waste water. According to the invention, for the biological/biofilm treatment of the activated sludge a biostage (2) with an aeration device (4) which can be switched off is arranged downstream of a preliminary sedimentation tank with a sludge reservoir (1) and a feed pipe (6). The biostage (2) is partially filled with growth bodies (5) having a colonizable area of at least 800 m<2> per m<3> of bulk volume and comprises a retention device (8) for retaining the growth bodies (5) in an obstruction-free manner. Disposed after the retention device (8) is a final sedimentation tank (3) which can be flowed through vertically and has a discharge (7), the parts of the plant (1 to 4) preferably being disposed in circular tanks. The retention device (8) can consist of a pipe in or over which a discharge pipe leads into the final sedimentation tank (3). The biostage (2) can further comprise a biofilter stage (9) into which lead the feed pipe from the preliminary sedimentation tank (1) and the feed pipe for returned sludge from the final sedimentation tank (3). The specific weight of the growth bodies can be greater or less than 1.0 g/cm<3>.