Device and method for biologically purifying waste water

摘要

Into the activated sludge tank (10) a catalyst is supplied. Here, components of the waste water are decomposed by a suspended degradation agent (11). The tank includes a plate pack (50) into or onto which the suspended agent sediments. It sinks as a sludge to the tank base (15). A forced recirculation system (20, 22) for the agent, accepts its thickened form, returning it as a suspension, back to the same treatment tank (10). An Independent claim is included for the corresponding method. Preferred features: The catalyst (sic) is air or oxygen, injected by nozzles. The agent (11) comprises biologically-active bacterial cultures or microorganisms, i.e. is recycled activated sludge, which convert the components of waste water into biologically-unobjectionable end products. A post-clarification (humus) tank is connected to the activated sludge tank. This separates any remaining agent, which is also recycled. This tank also includes plate separators. The recycle system (20, 22) includes a pump (or e.g. air lifter) and scraper operating together, to collect and transfer the activated sludge. The base under the plate pack slopes to reinforce sludge recycle. A further variant based on the foregoing principles is described.