Plant and process for advanced purification of effluent water from a biological sewage treatment plant

摘要

The apparatus (1) is intended for a very substantial purification of water which is present in the outflow (25) of a biological sewage treatment plant. This efflux water contains ammonium and suspended matter; it can also contain phosphate and substances containing biologically/chemically degradable carbon. The apparatus (1) includes a plurality of part-chambers and auxiliary devices, that is an aerated reaction chamber (3), a flocculation chamber (5), a separation chamber (6) for separating sludge and clear water, a return (65) of the sludge to the feed of the reaction chamber, a filter device (7) for the clear water connected downstream of the separation chamber, a return (95) by means of which the wash effluent of the filter device can be transported into the reaction chamber and metering devices (11, 12, 52) for adsorbents, precipitants and flocculation aids. It is provided that the constituents of the efflux water can be at least partially eliminated in the reaction chamber, that is by nitrification of the ammonium and if required by precipitation of the phosphate and by binding further constituents to adsorbents. In addition, it is provided that in the flocculation chamber - if required - suspended solid particles can be converted by flocculation aids into readily sedimentable floc structures. IMAGE