WATER TREATMENT DEVICE HAVING DISCS AND A ROTARY DRUM FILTER, AND CORRESPONDING PROCESS

The technique proposed here relates to a water treatment device comprising raw water inlet means (24), treated water discharge means (17, 28) and an essentially parallelepipedal frame (10) having a bottom and a cover element (11), said frame (10) defining at least: a biological treatment zone (12) accommodating a plurality of biological discs (16); and a filtration zone (13) accommodating at least one drum filter (21), at least one part of which has perforations, and sludge collecting means (33), said biological discs (16) and said drum filter (21) both being mounted essentially on the same axis (X) and having approximately the same outside diameters, the device further including means (22) for conveying a partly biologically purified flow coming from said biological treatment zone (12) within said drum filter (21). According to the technique proposed here, such a device includes means for declogging said perforations of said drum filter (21) which comprise at least means for blowing pressurized air on the periphery of said drum filter (21).